SUBSTITUTED PYRAZOLO[3,4-b]PYRIDIN-6-CARBOXYLIC ACIDS AND METHOD OF USE

ABSTRACT

The present invention provides for compounds of formula (I) 
     
       
         
         
             
             
         
       
     
     wherein R 1 , R 2 , R 3 , and R 4  have any of the values defined in the specification, and pharmaceutically acceptable salts thereof, that are useful as agents in the treatment of diseases and conditions mediated and modulated by CFTR, including cystic fibrosis, Sjögren&#39;s syndrome, pancreatic insufficiency, chronic obstructive lung disease, and chronic obstructive airway disease. Also provided are pharmaceutical compositions comprised of one or more compounds of formula (I).

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No. 62/239,475, filed Oct. 9, 2015, which is incorporated herein by reference for all purposes.

BACKGROUND OF THE INVENTION

Cystic fibrosis (CF) is a disease caused by mutations in the Or gene which induces defects in the CFTR protein, its production and/or its function. Cystic fibrosis is the most common fatal genetic disease in humans, and affects ˜0.04% of white individuals. For example, in the United States, about one in every 2,500 infants is affected, and up to 10 million people carry a single copy of the defective gene without apparent ill effects; moreover subjects bearing a single copy of the gene exhibit increased resistance to cholera and to dehydration resulting from diarrhea. In contrast, individuals with two copies of the CF associated gene suffer from the debilitating and fatal effects of CF, including chronic lung infections.

In cystic fibrosis patients, mutations in endogenous respiratory epithelial CFTR lead to a failure to confer chloride and bicarbonate permeability to epithelial cells in lung and other tissues, thus leading to reduced apical anion secretion and disruptions of the ion and fluid transport. This decrease in anion transport causes an enhanced mucus and pathogenic agent accumulation in the lung triggering microbial infections that ultimately cause death in CF patients.

Beyond respiratory disease, CF patients also suffer from gastrointestinal problems and pancreatic insufficiency that result in death if left untreated. Furthermore, female subjects with cystic fibrosis suffer from decreased fertility, whilst males with cystic fibrosis are infertile.

A variety of disease causing mutations has been identified through sequence analysis of the CFTR gene of CF chromosomes. ΔF508-CFTR, the most common CF mutation (present in at least 1 allele in ˜90% of CF patients) and occurring in approximately 70% of the cases of cystic fibrosis, contains a single amino acid deletion of phenylalanine 508. The F508del misfolding originates in the first nucleotide-binding domain (NBD1), which induces a global conformational change in CFTR through NBD1's interactions with other domains. This deletion prevents the nascent protein from folding correctly, whereby the protein in turn cannot exit the endoplasmic reticulum (ER) and being transported to the plasma membrane, and then is rapidly degraded. As a result, the number of channels present in the membrane is far less than in cells expressing wild-type CFTR. In addition to impaired trafficking, the mutation results in defective channel gating.

Accordingly, there is a need for novel compounds able to modulate CFTR. In particular, the present invention discloses compounds that may act as CFTR modulators for the treatment of cystic fibrosis. The present invention also provides methods for the preparation of these compounds, pharmaceutical compositions comprising these compounds and methods for the treatment of cystic fibrosis by administering the compounds of the invention.

SUMMARY

In one aspect the present invention provides for compounds of formula (I)

or a pharmaceutically acceptable salt thereof, wherein

-   -   R¹ is G^(1A), -G^(1B)-G^(1C), -G^(1B)-L^(1A)-G^(1C), C₁-C₆         haloalkyl, C₁-C₆ alkyl, —(C₁-C₆ alkylenyl)-CN, —(C₁-C₆         alkylenyl)-G^(1D), or -G^(1D)-O-benzyl;     -   L^(1A) is —O— or —O—(C₁-C₃ alkylenyl)-; wherein the left end of         the L^(1A) moiety is attached to G^(1B).     -   G^(1A) is phenyl, aryl, 5-6 membered monocyclic heteroaryl, 4-7         membered monocyclic heterocycle, fused bicyclic heterocycle, or         C₃-C₆ monocyclic cycloalkyl; wherein each G^(1A) is optionally         substituted with 1, 2, 3, or 4 independently selected R^(1a)         groups;     -   G^(1B) is phenyl or 5-6 membered monocyclic heteroaryl; wherein         each G^(1B) is optionally substituted with 1, 2, 3, or 4         independently selected R^(1b) groups;     -   G^(1C) is 4-7 membered monocyclic heterocycle which is         optionally substituted with 1, 2, 3, or 4 independently selected         R^(1c) groups;     -   G^(1D), at each occurrence, is a 4-7 membered monocyclic         heterocycle, 5-6 membered monocyclic heteroaryl, or a C₃-C₆         monocyclic cycloalkyl; wherein each G^(1D) is optionally         substituted with 1, 2, 3, or 4 independently selected R^(1d)         groups;     -   R² is C₂-C₄ alkenyl, C₁-C₆ alkyl, C₁-C₆ haloalkyl, —OR^(2xa),         —(C₁-C₆ alkylenyl)-OR^(2xb), —(C₁-C₆ alkylenyl)-N(R^(2xb))₂,         —C(O)OR^(2xb), —C(O)N(R^(2xb))₂, or -G^(2A);     -   R^(2xa) is hydrogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, or G^(2B);     -   R^(2xb), at each occurrence, is independently hydrogen, C₁-C₆         alkyl, or C₁-C₆ haloalkyl;     -   G^(2A) and G^(2B) are each independently 4-7 membered monocyclic         heterocycle or C₃-C₆ monocyclic cycloalkyl; wherein G^(2A) and         G^(2B) are each optionally substituted with 1, 2, or 3         independently selected R^(2a) groups;     -   R³ is halogen, G^(3A), -G^(3B)-L¹-G^(3C),         -G^(3B)-L³-G^(3C)-L⁴-G^(3F), —(C₁-C₆ alkylenyl)-G^(3E),         —OR^(3a), —N(R^(3a))(R^(3b)), —N(R^(3b))C(O)G^(3D), or         —C(O)G^(3D);     -   R^(3a), at each occurrence, is independently G^(3E), C₁-C₆         haloalkyl, or C₁-C₆ alkyl; wherein the C₁-C₆ haloalkyl and the         C₁-C₆ alkyl are each optionally substituted with one or two         substituents independently selected from the group consisting of         G^(3E), —OR^(3xa), —C(O)G^(3D), —N(R^(3xb))₂, and —S(O)₂R^(3xc);     -   R^(3xa), R^(3xb), and R^(3xc), at each occurrence, are each         independently hydrogen, C₁-C₆ haloalkyl, C₁-C₆ alkyl, G^(3E),         —(C₁-C₆ alkylenyl)-OR^(3ya), or —(C₁-C₆ alkylenyl)-N(R^(3ya))₂;         wherein R^(3ya), at each occurrence, is independently hydrogen,         C₁-C₆ alkyl, or C₁-C₆ haloalkyl;     -   R^(3b), at each occurrence, is hydrogen, C₁-C₆ alkyl, or C₁-C₆         haloalkyl;     -   L¹ is a bond, C₁-C₆ alkylenyl, (C₁-C₆ alkylenyl)_(r)-L²-(C₁-C₆         alkylenyl)_(s), or O—(C₁-C₆ alkylenyl)-C(O), wherein the left         end of the L¹ moiety is attached to G^(3B);     -   L² is O, N(R^(x)), C(O), N(R^(x))C(O), or C(O)N(R^(x)); wherein         each R^(x) is independently hydrogen, C₁-C₆ alkyl, or C₁-C₆         haloalkyl;     -   L³ is a bond or C₁-C₆ alkylenyl;     -   L⁴ is a bond, C₁-C₆ alkylenyl, O, N(R^(2x)), C(O),         N(R^(2x))C(O), or C(O)N(R^(2x)); wherein each R^(2x) is         independently hydrogen, C₁-C₆ alkyl, or C₁-C₆ haloalkyl;     -   r is 0 or 1;     -   s is 0 or 1;     -   G^(3A), G^(3B), and G^(3C), are each independently C₃-C₁₁         cycloalkyl, phenyl, 5-6 membered monocyclic heteroaryl, or 4-11         membered heterocycle, wherein G^(3A), G^(3B), and G^(3C) are         each optionally substituted with 1, 2, 3, or 4 independently         selected R^(e) groups;     -   G^(3D), at each occurrence, is 4-7 membered monocyclic         heterocycle which is optionally substituted with 1, 2, 3, or 4         independently selected R^(e) groups;     -   G^(3E), at each occurrence, is independently C₃-C₈ monocyclic         cycloalkyl or 4-11 membered heterocycle; wherein each G^(3E) is         optionally substituted with 1, 2, 3, or 4 substituents         independently selected from the group consisting of R^(e) and         G^(3F);     -   G^(3F), at each occurrence, is independently a 4-7 membered         monocyclic heterocycle or a C₃-C₆ monocyclic cycloalkyl; wherein         each G^(3F) is optionally substituted with 1, 2, 3, or 4         independently selected R^(e) groups;     -   R^(e), at each occurrence, is independently C₂-C₆ alkenyl, C₂-C₆         alkynyl, C₁-C₆ alkyl, C₁-C₆ haloalkyl, halogen, oxo, —CN, —N₃,         NO₂, —OR^(f), —OC(O)R^(g), —OC(O)NR^(f)R^(h), —SR^(f),         —S(O)₂R^(f), —S(O)₂NR^(f)R^(h), —C(O)R^(f), —C(O)OR^(f),         —C(O)NR^(f)R^(h), —C(O)N(R^(h))S(O)₂R^(f), —N(R^(f))₂,         —N(R^(h))C(O)R^(f), —N(R^(h))S(O)₂R^(g), —N(R^(h))C(O)O(R^(g)),         —N(R^(h))C(O)NR^(f)R^(h), or —N(R^(h))S(O)₂NR^(f)R^(h); wherein         the C₁-C₆ haloalkyl and the C₁-C₆ alkyl are each optionally         substituted with 1 or 2 substituents independently selected from         the group consisting of halogen, —CN, NO₂, —OR^(f), —OC(O)R^(g),         —OC(O)NR^(f)R^(h), —SR^(f), —S(O)₂R^(f), —S(O)₂NR^(f)R^(h),         —C(O)R, —C(O)OR, —C(O)NR^(f)R^(h), —C(O)N(R^(h))S(O)₂R^(f),         —N(R^(f))₂, —N(R^(h))C(O)R^(f), —N(R^(h))S(O)₂R^(g),         —N(R^(h))C(O)O(R^(g)), —N(R^(h))C(O)NR^(f)R^(h), and         —N(R^(h))S(O)₂NR^(f)R^(h);     -   R^(f), at each occurrence, is independently hydrogen, C₁-C₆         alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₁-C₆ haloalkyl, —(C₁-C₆         alkylenyl)-CN, —(C₁-C₆ alkylenyl)-OR^(m), —(C₁-C₆         alkylenyl)-OC(O)R^(n), —(C₁-C₆ alkylenyl)-OC(O)N(R^(m))₂,         —(C₁-C₆ alkylenyl)-SR^(m), —(C₁-C₆ alkylenyl)-S(O)₂R^(m),         —(C₁-C₆ alkylenyl)-S(O)₂N(R^(m))₂, —(C₁-C₆ alkylenyl)-C(O)R^(m),         —(C₁-C₆ alkylenyl)-C(O)OR^(m), —(C₁-C₆ alkylenyl)-C(O)N(R^(m))₂,         —(C₁-C₆ alkylenyl)-C(O)N(R^(m))S(O)₂R^(n), —(C₁-C₆         alkylenyl)-N(R^(m))₂, —(C₁-C₆ alkylenyl)-N(R^(m))C(O)R^(n),         —(C₁-C₆ alkylenyl)-N(R^(m))S(O)₂R^(n), —(C₁-C₆         alkylenyl)-N(R^(m))C(O)O(R^(n)), —(C₁-C₆         alkylenyl)-N(R^(m))C(O)N(R^(m))₂, or —(C₁-C₆         alkylenyl)-N(R^(m))S(O)₂N(R^(m))₂;     -   R^(g), at each occurrence, is independently C₁-C₆ alkyl, C₂-C₆         alkenyl, C₂-C₆ alkynyl, C₁-C₆ haloalkyl, —(C₁-C₆ alkylenyl)-CN,         —(C₁-C₆ alkylenyl)-OR^(m), —(C₁-C₆ alkylenyl)-OC(O)R^(n),         —(C₁-C₆ alkylenyl)-OC(O)N(R^(m))₂, —(C₁-C₆ alkylenyl)-SR^(m),         —(C₁-C₆ alkylenyl)-S(O)₂R^(m), —(C₁-C₆         alkylenyl)-S(O)₂N(R^(m))₂, alkylenyl)-C(O)R^(m), —(C₁-C₆         alkylenyl)-C(O)OR^(m), —(C₁-C₆ alkylenyl)-C(O)N(R^(m))₂, —(C₁-C₆         alkylenyl)-C(O)N(R^(m))S(O)₂R^(n), —(C₁-C₆ alkylenyl)-N(R^(m))₂,         —(C₁-C₆ alkylenyl)-N(R^(m))C(O)R^(n), —(C₁-C₆         alkylenyl)-N(R^(m))S(O)₂R^(n), —(C₁-C₆         alkylenyl)-N(R^(m))C(O)O(R″), —(C₁-C₆         alkylenyl)-N(R^(m))C(O)N(R^(m))₂, or —(C₁-C₆         alkylenyl)-N(R^(m))S(O)₂N(R^(m))₂;     -   R^(h), at each occurrence, is independently hydrogen, C₁-C₆         alkyl, C₁-C₆ haloalkyl, or —(C₁-C₆ alkylenyl)-OR^(m);     -   R^(1a), R^(1b), R^(1c), R^(1d), and R^(2a), at each occurrence,         are each independently C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆         alkynyl, halogen, C₁-C₆ haloalkyl, oxo, —CN, NO₂, —OR^(m),         —OC(O)R^(n), —OC(O)N(R^(m))₂, —SR^(m), —S(O)₂R^(m),         —S(O)₂N(R^(m))₂, —C(O)R^(m), —C(O)OR^(m), —C(O)N(R^(m))₂,         —C(O)N(R^(m))S(O)₂R^(n), —N(R^(m))₂, —N(R^(m))(alkoxyalkyl),         —N(alkoxyalkyl)₂, —N(R^(m))C(O)R^(n), —N(R^(m))S(O)₂R^(n),         —N(R^(m))C(O)O(R^(n)), —N(R^(m))C(O)N(R^(m))₂,         —N(R^(m))S(O)₂N(R^(m))₂, —(C₁-C₆ alkylenyl)-CN, —(C₁-C₆         alkylenyl)-OR^(m), —(C₁-C₆ alkylenyl)-OC(O)R^(n), —(C₁-C₆         alkylenyl)-OC(O)N(R^(m))₂, —(C₁-C₆ alkylenyl)-SR^(m), —(C₁-C₆         alkylenyl)-S(O)₂R^(m), —(C₁-C₆ alkylenyl)-S(O)₂N(R^(m))₂,         —(C₁-C₆ alkylenyl)-C(O)R^(m), —(C₁-C₆ alkylenyl)-C(O)OR^(m),         —(C₁-C₆ alkylenyl)-C(O)N(R^(m))₂, —(C₁-C₆         alkylenyl)-C(O)N(R^(m))S(O)₂R^(n), —(C₁-C₆ alkylenyl)-N(R^(m))₂,         —(C₁-C₆ alkylenyl)-N(R^(m))C(O)R^(n), —(C₁-C₆         alkylenyl)-N(R^(m))S(O)₂R^(n), —(C₁-C₆         alkylenyl)-N(R^(m))C(O)O(R^(n)), —(C₁-C₆         alkylenyl)-N(R^(m))C(O)N(R^(n))₂, or —(C₁-C₆         alkylenyl)-N(R^(m))S(O)₂N(R^(n))₂;     -   R^(m), at each occurrence, is independently hydrogen, C₁-C₆         alkyl, or C₁-C₆ haloalkyl;     -   R^(n), at each occurrence, is independently C₁-C₆ alkyl or C₁-C₆         haloalkyl; and     -   R⁴ is hydrogen, C₁-C₃ alkyl, or C₁-C₃ haloalkyl;     -   with the proviso that when R¹ is C₁-C₆ alkyl or G^(1A), wherein         G^(1A) is optionally substituted phenyl, optionally substituted         5-6 membered monocyclic heteroaryl, or optionally substituted         4-7 membered monocyclic heterocycle, R² is C₁-C₆ alkyl, and R³         is G^(3A), then G^(3A) is not optionally substituted phenyl or         optionally substituted 5-6 membered monocyclic heteroaryl.

Another aspect of the invention relates to pharmaceutical compositions comprising a compound of the invention, and a pharmaceutical carrier. Such compositions can be administered in accordance with a method of the invention, typically as part of a therapeutic regimen for treatment or prevention of conditions and disorders related to Cystic Fibrosis Transmembrane Conductance Regulator activity. In a particular aspect, the pharmaceutical compositions may additionally comprise further therapeutically active ingredients suitable for use in combination with the compounds of the invention. In a more particular aspect, the further therapeutically active ingredient is an agent for the treatment of cystic fibrosis.

Moreover, the compounds of the invention, useful in the pharmaceutical compositions and treatment methods disclosed herein, are pharmaceutically acceptable as prepared and used.

Yet another aspect of the invention relates to a method for treating, or preventing conditions and disorders related to Cystic Fibrosis Transmembrane Conductance Regulator activity in mammals. More particularly, the method is useful for treating or preventing conditions and disorders related to cystic fibrosis, Sjögren's syndrome, pancreatic insufficiency, chronic obstructive lung disease, or chronic obstructive airway disease. Accordingly, the compounds and compositions of the invention are useful as a medicament for treating or preventing Cystic Fibrosis Transmembrane Conductance Regulator modulated disease.

The compounds, compositions comprising the compounds, methods for making the compounds, and methods for treating or preventing conditions and disorders by administering the compounds are further described herein.

In a particular aspect, the compounds of the invention are provided for use in the treatment of cystic fibrosis. In a particular aspect, the compounds of the invention are provided for use in the treatment of cystic fibrosis caused by class I, II, III, IV, V, and/or VI mutations.

The present invention also provides pharmaceutical compositions comprising a compound of the invention, and a suitable pharmaceutical carrier for use in medicine. In a particular aspect, the pharmaceutical composition is for use in the treatment of cystic fibrosis.

These and other objects of the invention are described in the following paragraphs. These objects should not be deemed to narrow the scope of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Described herein are compounds of formula (I)

wherein R¹, R², R³, and R⁴ are defined above in the Summary of the Invention and below in the Detailed Description. Further, compositions comprising such compounds and methods for treating conditions and disorders using such compounds and compositions are also described.

Compounds included herein may contain one or more variable(s) that occur more than one time in any substituent or in the formulae herein. Definition of a variable on each occurrence is independent of its definition at another occurrence. Further, combinations of sub stituents are permissible only if such combinations result in stable compounds. Stable compounds are compounds, which can be isolated from a reaction mixture.

DEFINITIONS

It is noted that, as used in this specification and the intended claims, the singular form “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a compound” includes a single compound as well as one or more of the same or different compounds; reference to “a pharmaceutically acceptable carrier” means a single pharmaceutically acceptable carrier as well as one or more pharmaceutically acceptable carriers, and the like.

As used in the specification and the appended claims, unless specified to the contrary, the following terms have the meaning indicated:

The term “alkenyl” as used herein, means a straight or branched hydrocarbon chain containing from 2 to 10 carbons and containing at least one carbon-carbon double bond. The term “C₂-C₆ alkenyl” means an alkenyl group containing 2-6 carbon atoms. Non-limiting examples of C₂-C₆ alkenyl include buta-1,3-dienyl, ethenyl, 2-propenyl, 2-methyl-2-propenyl, 3-butenyl, 4-pentenyl, and 5-hexenyl.

The term “alkoxy” as used herein, means a C₁-C₆ alkyl group, as defined herein, appended to the parent molecular moiety through an oxygen atom. Non-limiting examples of alkoxy include methoxy, ethoxy, propoxy, 2-propoxy, butoxy, tert-butoxy, pentyloxy, and hexyloxy.

The term “alkoxyalkyl” as used herein, means an alkoxy group, as defined herein, appended to the parent molecular moiety through a C₁-C₆ alkyl group, as defined herein. Non-limiting examples of alkoxyalkyl include tert-butoxymethyl, 2-ethoxyethyl, 2-methoxyethyl, and methoxymethyl.

The term “alkyl” as used herein, means a saturated, straight or branched hydrocarbon chain radical. In some instances, the number of carbon atoms in an alkyl moiety is indicated by the prefix “C_(x)-C_(y)”, wherein x is the minimum and y is the maximum number of carbon atoms in the substituent. Thus, for example, “C₁-C₆ alkyl” means an alkyl substituent containing from 1 to 6 carbon atoms and “C₁-C₃ alkyl” means an alkyl substituent containing from 1 to 3 carbon atoms. Representative examples of alkyl include, but are not limited to, methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 3,3-dimethylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, 1-methylpropyl, 2-methylpropyl, 1-ethylpropyl, and 1,2,2-trimethylpropyl. The terms “alkyl,” “C₁-C₆ alkyl,” “C₁-C₄ alkyl,” and “C₁-C₃ alkyl” used herein are unsubstituted, unless otherwise indicated.

The term “alkylene” or “alkylenyl” means a divalent radical derived from a straight or branched, saturated hydrocarbon chain, for example, of 1 to 10 carbon atoms or of 1 to 6 carbon atoms (C₁-C₆ alkylenyl) or of 1 to 4 carbon atoms or of 1 to 3 carbon atoms (C₁-C₃ alkylenyl) or of 2 to 6 carbon atoms (C₂-C₆ alkylenyl). Examples of C₁-C₆ alkylenyl include, but are not limited to, —CH₂—, —CH₂CH₂—, —C(CH₃)₂—CH₂CH₂CH₂—, —C(CH₃)₂—CH₂CH₂—, —CH₂CH₂CH₂CH₂—, and —CH₂CH(CH₃)CH₂—.

The term “C₂-C₆ alkynyl” as used herein, means a straight or branched chain hydrocarbon radical containing from 2 to 6 carbon atoms and containing at least one carbon-carbon triple bond. Representative examples of C₂-C₆ alkynyl include, but are not limited, to acetylenyl, 1-propynyl, 2-propynyl, 3-butynyl, 2-pentynyl, and 1-butynyl.

The term “aryl” as used herein, means a phenyl fused to a C₃-C₆ monocyclic cycloalkyl or a phenyl fused to a C₄-C₇ monocyclic cycloalkenyl. Example of an aryl group includes, but is not limited to, bicyclo[4.2.0]octa-1,3,5-trien-3-yl.

The term “C₃-C₁₁ cycloalkyl” as used herein, means a hydrocarbon ring radical containing 3-11 carbon atoms, zero heteroatom, and zero double bond. The C₃-C₁₁ cycloalkyl group may be a single-ring (monocyclic) or have two or more rings (bicyclic or polycyclic). Monocyclic cycloalkyl groups typically contain from 3 to 8 carbon ring atoms (C₃-C₈ monocyclic cycloalkyl), and even more typically 3-6 carbon ring atoms (C₃-C₆ monocyclic cycloalkyl). Examples of monocyclic cycloalkyls include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Polycyclic cycloalkyl groups contain two or more rings, and bicyclic cycloalkyls contain two rings. In certain embodiments, the polycyclic cycloalkyl groups contain 2 or 3 rings. The rings within the polycyclic and the bicyclic cycloalkyl groups may be in a bridged, fused, or spiro orientation, or combinations thereof. In a spirocyclic cycloalkyl, one atom is common to two different rings. An example of a spirocyclic cycloalkyl is spiro[4.5]decane. In a bridged cycloalkyl, the rings share at least two non-adjacent atoms. Examples of bridged cycloalkyls include, but are not limited to, bicyclo[2.2.2]octyl, bicyclo[3.2.1]octyl, bicyclo[3.1.1]heptyl, bicyclo[2.2.1]heptyl, bicyclo[3.2.2]nonyl, bicyclo[3.3.1]nonyl, bicyclo[4.2.1]nonyl, tricyclo[3.3.1.0^(3.7)]nonyl(octahydro-2,5-methanopentalenyl or noradamantyl), tricyclo[3.3.1.1^(3.7)]decyl(adamantyl), and tricyclo[4.3.1.1^(3.8)]undecyl(homoadamantyl). In a fused ring cycloalkyl, the rings share one common bond. Examples of fused-ring cycloalkyl include, but not limited to, decalin (decahydronaphthyl) and bicyclo[2.2.0]octyl.

The term “C₄-C₇ monocyclic cycloalkenyl” as used herein, means cyclobutenyl, cyclopentenyl, cyclohexenyl, and cycloheptyl.

The term “halo” or “halogen” as used herein, means Cl, Br, I, and F.

The term “haloalkyl” as used herein, means an alkyl group, as defined herein, in which one, two, three, four, five or six hydrogen atoms are replaced by halogen. The term “C₁-C₆ haloalkyl” means a C₁-C₆ alkyl group, as defined herein, in which one, two, three, four, five, or six hydrogen atoms are replaced by halogen. The term “C₁-C₃ haloalkyl” means a C₁-C₃ alkyl group, as defined herein, in which one, two, three, four, or five hydrogen atoms are replaced by halogen. Representative examples of haloalkyl include, but are not limited to, chloromethyl, 2-fluoroethyl, 2,2-difluoroethyl, fluoromethyl, 2,2,2-trifluoroethyl, trifluoromethyl, difluoromethyl, pentafluoroethyl, 2-chloro-3-fluoropentyl, trifluorobutyl, and trifluoropropyl. The terms “haloalkyl,” “C₁-C₃ haloalkyl,” and “C₁-C₆ haloalkyl” used herein are unsubstituted, unless otherwise indicated.

The term “4-11 membered heterocycle” as used herein, means a hydrocarbon ring radical of 4-11 carbon ring atoms wherein at least one carbon atom is replaced by a heteroatom(s) independently selected from the group consisting of O, N, and S. The 4-11 membered heterocycle ring may be a single ring (monocyclic) or have two or more rings (bicyclic or polycyclic). In certain embodiments, the monocyclic heterocycle is a four-, five-, six-, seven-, or eight-membered hydrocarbon ring wherein at least one carbon ring atom is replaced by a heteroatom(s) independently selected from the group consisting of O, N, and S. In certain embodiments, the monocyclic heterocycle is a 4-7 membered hydrocarbon ring wherein at least one carbon ring atom is replaced by a heteroatom(s). A four-membered monocyclic heterocycle contains zero or one double bond, and one heteroatom selected from the group consisting of O, N, and S. A five-membered monocyclic heterocycle contains zero or one double bond and one, two, or three heteroatoms selected from the group consisting of O, N, and S. Examples of five-membered monocyclic heterocycles include those containing in the ring: 1 O; 1 S; 1 N; 2 N; 3 N; 1 S and 1 N; 1 S, and 2 N; 1 O and 1 N; or 1 O and 2 N. Non limiting examples of 5-membered monocyclic heterocyclic groups include 1,3-dioxolanyl, tetrahydrofuranyl, dihydrofuranyl, tetrahydrothienyl, dihydrothienyl, imidazolidinyl, oxazolidinyl, imidazolinyl, imidazolidinyl, isoxazolidinyl, pyrazolidinyl, pyrazolinyl, pyrrolidinyl, 2-pyrrolinyl, 3-pyrrolinyl, tetrahydrothienyl, thiazolinyl, and thiazolidinyl. A six-membered monocyclic heterocycle contains zero, one, or two double bonds and one, two, or three heteroatoms selected from the group consisting of O, N, and S. Examples of six-membered monocyclic heterocycles include those containing in the ring: 1 O; 2 O; 1 S; 2 S; 1 N; 2 N; 3 N; 1 S, 1 O, and 1 N; 1 S and 1 N; 1 S and 2 N; 1 S and 1 O; 1 S and 2 O; 1 O and 1 N; and 1 O and 2 N. Examples of six-membered monocyclic heterocycles include dihydropyridinyl, 1,6-dihydropyrimidinyl, dihydropyranyl, 1,3-dioxanyl, 1,4-dioxanyl, 1,4-dithianyl, hexahydropyrimidine, imidazolidinyl, morpholinyl, oxazolidinyl, piperazinyl, piperidinyl, tetrahydropyranyl, 1,2,3,6-tetrahydropyridinyl, tetrahydrothiopyranyl, thiomorpholinyl, thioxanyl, and trithianyl. Seven- and eight-membered monocyclic heterocycles contains zero, one, two, or three double bonds and one, two, or three heteroatoms selected from the group consisting of O, N, and S. Examples of monocyclic heterocycles include, but are not limited to, azetidinyl, azepanyl, aziridinyl, 1,4-diazepanyl, 1,2-dihydropyridinyl, 1,6-dihydropyrimidinyl, dihydropyranyl, 1,3-dioxanyl, 1,3-dioxolanyl, 1,4-dioxanyl, 1,3-dithiolanyl, 1,3-dithianyl, imidazolinyl, imidazolidinyl, isothiazolinyl, isothiazolidinyl, isoxazolinyl, isoxazolidinyl, morpholinyl, 1,4-oxazepanyl, oxadiazolinyl, oxadiazolidinyl, oxazolinyl, oxazolidinyl, oxetanyl, piperazinyl, piperidinyl, pyranyl, pyrazolinyl, pyrazolidinyl, pyrrolinyl, pyrrolidinyl, tetrahydrofuranyl, tetrahydropyridinyl, tetrahydropyranyl, tetrahydrothienyl, thiadiazolinyl, thiadiazolidinyl, thiazolinyl, thiazolidinyl, thiomorpholinyl, thiopyranyl, and trithianyl. Polycyclic heterocycle groups contain two or more rings, and bicyclic heterocycles contain two rings. In certain embodiments, the polycyclic heterocycle groups contain 2 or 3 rings. The rings within the polycyclic and the bicyclic heterocycle groups may be in a bridged, fused, or spiro orientation, or combinations thereof. In a spirocyclic heterocycle, one atom is common to two different rings. Non limiting examples of the spirocyclic heterocycle include 2-azaspiro[3.3]heptyl, 5-azaspiro[2.4]heptyl, 5-azaspiro[2.5]octyl, 2-azaspiro[3.5]nonyl, 2-azaspiro[3.4]octyl, 3-azaspiro[5.5]undecyl, 5-azaspiro[3.4]octyl, 2-oxaspiro[3.3]heptyl, 2-oxa-6-azaspiro[3.3]heptyl, 2-oxa-6-azaspiro[3.4]octyl, 6-oxa-2-azaspiro[3.4]octyl, 6-azaspiro[3.4]octyl, 7-azaspiro[3.5]nonyl, 8-azaspiro[4.5]decyl, 1-oxa-7-azaspiro[4.4]nonyl, 1-oxa-7-azaspiro[3.5]nonyl, 1-oxa-8-azaspiro[4.5]decyl, 1-oxa-3,8-diazaspiro[4.5]decyl, 1-oxa-4,9-diazaspiro[5.5]undecyl, 2-oxa-7-azaspiro[3.5]nonyl, 5-oxa-2-azaspiro[3.5]nonyl, 5-oxa-2-azaspiro[3.4]octyl, 6-oxa-2-azaspiro[3.5]nonyl, 7-oxa-2-azaspiro[3.5]nonyl, 8-oxa-2-azaspiro[4.5]decyl, 2,7-diazaspiro[4.4]nonyl, 1,4-dioxa-8-azaspiro[4.5]decyl, 1,4-dioxa-7-azaspiro[4.4]nonyl, 1,3,8-triazaspiro[4.5]decyl, 2-oxa-5,8-diazaspiro[3.5]nonyl, 2,8-diazaspiro[4.5]decyl and 3,9-diazaspiro[5.5]undecyl. In a fused ring heterocycle, the rings share one common bond. Examples of fused bicyclic heterocycles are a 4-6 membered monocyclic heterocycle fused to a phenyl group, or a 4-6 membered monocyclic heterocycle fused to a C₃-C₆ monocyclic cycloalkyl, or a 4-6 membered monocyclic heterocycle fused to a C₄-C₇ monocyclic cycloalkenyl, or a 4-6 membered monocyclic heterocycle fused to a 4-7 membered monocyclic heterocycle. Examples of fused bicyclic heterocycles include, but are not limited to, 3-azabicyclo[3.1.0]hexyl, benzo[d][1,3]dioxolyl, benzopyranyl, benzothiopyranyl, indolinyl, decahydropyrrolo[3,4-b]azepinyl, 2,3-dihydrobenzofuranyl, 2,3-dihydrobenzothienyl, 2,3-dihydro-1H-indolyl, isoindolinyl, 3,4-dihydroisoquinolin-2(1H)-yl, 2,3,4,6-tetrahydro-1H-pyrido[1,2-a]pyrazin-2-yl, hexahydropyrano[3,4-b][1,4]oxazin-1(5H)-yl, hexahydropyrrolo[3,4-b][1,4]oxazin-6(2H)-yl, hexahydrocyclopenta[c]pyrrol-3a(1H)-yl, hexahydro-1H-oxazolo[3,4-a]pyrazinyl, octahydroimidazo[1,5-a]pyrazinyl, hexahydropyrrolo[1,2-a]pyrazin-2(1H)-yl, octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl, and octahydropyrrolo[3,4-c]pyrrolyl. In a bridged heterocycle, the rings share at least two non-adjacent atoms. Examples of such bridged heterocycles include, but are not limited to, azabicyclo[2.2.1]heptyl (including 2-azabicyclo[2.2.1]hept-2-yl), 2-oxa-5-azabicyclo[2.2.1]heptyl, 8-azabicyclo[3.2.1]octyl, octahydro-2,5-epoxypentalene, 8-oxa-3-azabicyclo[3.2.1]octyl, hexahydro-1H-1,4-methanocyclopenta[c]furan, aza-admantane (1-azatricyclo[3.3.1.1^(3.7)]decane), and oxa-adamantane (2-oxatricyclo[3.3.1.1^(3.7)]decane). The nitrogen and sulfur heteroatoms in the heterocycle rings may optionally be oxidized (e.g. 1,1-dioxidotetrahydrothienyl, 1,1-dioxido-1,2-thiazolidinyl, 1,1-dioxidothiomorpholinyl)) and the nitrogen atoms may optionally be quaternized.

The term “5-11 membered heteroaryl” as used herein, means a monocyclic heteroaryl and a bicyclic heteroaryl. The monocyclic heteroaryl is a five- or six-membered ring. The five-membered ring contains two double bonds. The five membered ring may contain one heteroatom selected from O or S; or one, two, three, or four nitrogen atoms and optionally one oxygen or one sulfur atom. The six-membered ring contains three double bonds and one, two, three or four nitrogen atoms. Examples of 5-6 membered monocyclic heteroaryl include, but are not limited to, furanyl, imidazolyl, isoxazolyl, isothiazolyl, oxadiazolyl, 1,3-oxazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, pyrazolyl, pyrrolyl, tetrazolyl, thiadiazolyl, 1,3-thiazolyl, thienyl, triazolyl, and triazinyl. The bicyclic heteroaryl consists of a monocyclic heteroaryl fused to a phenyl, or a monocyclic heteroaryl fused to a C₃-C₆ monocyclic cycloalkyl, or a monocyclic heteroaryl fused to C₄-C₇ monocyclic cycloalkenyl, or a monocyclic heteroaryl fused to a monocyclic heteroaryl, or a monocyclic heteroaryl fused to a 4-7 membered monocyclic heterocycle. Representative examples of bicyclic heteroaryl groups include, but are not limited to, benzofuranyl, benzothienyl, benzoxazolyl, benzimidazolyl, benzoxadiazolyl, phthalazinyl, 2,6-dihydropyrrolo[3,4-c]pyrazol-5(4H)-yl, 6,7-dihydro-pyrazolo[1,5-a]pyrazin-5(4H)-yl, 6,7-dihydro-1,3-benzothiazolyl, imidazo[1,2-a]pyridinyl, indazolyl, indolyl, isoindolyl, isoquinolinyl, naphthyridinyl, pyridoimidazolyl, quinolinyl, 2,4,6,7-tetrahydro-5H-pyrazolo[4,3-c]pyridin-5-yl, thiazolo[5,4-b]pyridin-2-yl, thiazolo[5,4-d]pyrimidin-2-yl, and 5,6,7,8-tetrahydroquinolin-5-yl. The nitrogen atom in the heteroaryl rings may optionally be oxidized and may optionally be quaternized.

The phenyl, the cycloalkyls, the cycloalkenyls, the heterocycles, and the heteroaryls, including the exemplary rings, are optionally substituted unless otherwise indicated; and are attached to the parent molecular moiety through any substitutable atom contained within the ring system.

The term “heteroatom” as used herein, means a nitrogen, oxygen, and sulfur.

The term “oxo” as used herein, means a═O group.

The term “radiolabel” means a compound of the invention in which at least one of the atoms is a radioactive atom or a radioactive isotope, wherein the radioactive atom or isotope spontaneously emits gamma rays or energetic particles, for example alpha particles or beta particles, or positrons. Examples of such radioactive atoms include, but are not limited to, ³H (tritium), ¹⁴C, ¹¹C, ¹⁵O, ¹⁸F, ³⁵ s, ¹²³I and ¹²⁵I.

A moiety is described as “substituted” when a non-hydrogen radical is in the place of hydrogen radical of any substitutable atom of the moiety. Thus, for example, a substituted heterocycle moiety is a heterocycle moiety in which at least one non-hydrogen radical is in the place of a hydrogen radical on the heterocycle. It should be recognized that if there are more than one substitution on a moiety, each non-hydrogen radical may be identical or different (unless otherwise stated).

If a moiety is described as being “optionally substituted,” the moiety may be either (1) not substituted or (2) substituted. If a moiety is described as being optionally substituted with up to a particular number of non-hydrogen radicals, that moiety may be either (1) not substituted; or (2) substituted by up to that particular number of non-hydrogen radicals or by up to the maximum number of substitutable positions on the moiety, whichever is less. Thus, for example, if a moiety is described as a heteroaryl optionally substituted with up to 3 non-hydrogen radicals, then any heteroaryl with less than 3 substitutable positions would be optionally substituted by up to only as many non-hydrogen radicals as the heteroaryl has substitutable positions. To illustrate, tetrazolyl (which has only one substitutable position) would be optionally substituted with up to one non-hydrogen radical. To illustrate further, if an amino nitrogen is described as being optionally substituted with up to 2 non-hydrogen radicals, then a primary amino nitrogen will be optionally substituted with up to 2 non-hydrogen radicals, whereas a secondary amino nitrogen will be optionally substituted with up to only 1 non-hydrogen radical.

The terms “treat”, “treating”, and “treatment” refer to a method of alleviating or abrogating a disease and/or its attendant symptoms. In certain embodiments, “treat,” “treating,” and “treatment” refer to ameliorating at least one physical parameter, which may not be discernible by the subject. In yet another embodiment, “treat”, “treating”, and “treatment” refer to modulating the disease or disorder, either physically (for example, stabilization of a discernible symptom), physiologically (for example, stabilization of a physical parameter), or both. In a further embodiment, “treat”, “treating”, and “treatment” refer to slowing the progression of the disease or disorder.

The terms “prevent”, “preventing”, and “prevention” refer to a method of preventing the onset of a disease and/or its attendant symptoms or barring a subject from acquiring a disease. As used herein, “prevent”, “preventing” and “prevention” also include delaying the onset of a disease and/or its attendant symptoms and reducing a subject's risk of acquiring or developing a disease or disorder.

The phrase “therapeutically effective amount” means an amount of a compound, or a pharmaceutically acceptable salt thereof, sufficient to prevent the development of or to alleviate to some extent one or more of the symptoms of the condition or disorder being treated when administered alone or in conjunction with another therapeutic agent for treatment in a particular subject or subject population. The “therapeutically effective amount” may vary depending on the compound, the disease and its severity, and the age, weight, health, etc., of the subject to be treated. For example in a human or other mammal, a therapeutically effective amount may be determined experimentally in a laboratory or clinical setting, or may be the amount required by the guidelines of the United States Food and Drug Administration, or equivalent foreign agency, for the particular disease and subject being treated.

The term “subject” is defined herein to refer to animals such as mammals, including, but not limited to, primates (e.g., humans), cows, sheep, goats, pigs, horses, dogs, cats, rabbits, rats, mice and the like. In one embodiment, the subject is a human. The terms “human,” “patient,” and “subject” are used interchangeably herein.

The term ‘one or more’ refers to one to four. In one embodiment it refers to one or three. In another embodiment it refers to one to three. In a further embodiment it refers to one to two. In yet other embodiment it refers to two. In yet other further embodiment it refers to one.

As used herein, “Class I mutation(s)” refers to mutations which interfere with protein synthesis. They result in the introduction of a premature signal of termination of translation (stop codon) in the mRNA. The truncated CFTR proteins are unstable and rapidly degraded, so, the net effect is that there is no protein at the apical membrane. In particular, Class I mutation(s) refers to p.Gly542X (G542X), W1282X, c.489+1G>T (621+1G>T), or c.579+1G>T (711+1G>T) mutation. More particularly, Class I mutation(s) refers to G542X; or W1282X mutations.

As used herein, “Class II mutation(s)” refers to mutations which affect protein maturation. These lead to the production of a CFTR protein that cannot be correctly folded and/or trafficked to its site of function on the apical membrane. In particular, Class II mutation(s) refers to p.Phe508del (F508del), p.Ile507del, or p.Asn1303Lys (N1303K) mutations. More particularly, Class II mutation(s) refers to F508del or N1303K mutations.

As used herein, “Class III mutation(s)” refers to mutations which alter the regulation of the CFTR channel. The mutated CFTR protein is properly trafficked and localized to the plasma membrane but cannot be activated, or it cannot function as a chloride channel. In particular, Class III mutation(s) refers to p.Gly551Asp (G551D), G551S, R553G, G1349D, S1251N, G178R, S549N mutations. More particularly, Class III mutation(s) refers to G551D, R553G, G1349D, S1251N, G178R, or S549N mutations.

As used herein, “Class IV mutation(s)” refers to mutations which affect chloride conductance. The CFTR protein is correctly trafficked to the cell membrane but generates reduced chloride flow or a “gating defect” (most are missense mutations located within the membrane-spanning domain). In particular, Class IV mutation(s) refers to p.Arg117His (R117H), R347P, or p.Arg334Trp (R334W) mutations.

As used herein, “Class V mutation(s)” refers to mutations which reduce the level of normally functioning CFTR at the apical membrane or result in a “conductance defect” (for example partially aberrant splicing mutations or inefficient trafficking missense mutations). In particular, Class V mutation(s) refers to c.1210-12T[5] (5T allele), c.S3140-26A>G (3272-26A>G), c.3850-2477C>T (3849+10kbC>T) mutations.

As used herein, “Class VI mutation(s)” refers to mutations which decrease the stability of the CFTR which is present or which affect the regulation of other channels, resulting in inherent instability of the CFTR protein. In effect, although functional, the CFTR protein is unstable at the cell surface and it is rapidly removed and degraded by cell machinery. In particular, Class VI mutation(s) refers to Rescued F508del, 120del23, N287Y, 4326delITC, or 4279insA mutations. More particularly, Class VI mutation(s) refers to Rescued F508del mutations.

Compounds

Compounds of the invention have the general formula (I) as described above.

Particular values of variable groups in compounds of formula (I) are as follows. Such values may be used where appropriate with any of the other values, definitions, claims or embodiments defined hereinbefore or hereinafter.

In certain embodiments of formula (I), R¹ is —(C₁-C₆ alkylenyl)-CN, —(C₁-C₆ alkylenyl)-G^(1D), or -G^(1D)-O-benzyl.

In certain embodiments of formula (I), R¹ is G^(1A), -G^(1B)-G^(1C), -G^(1B)-L^(1A)-G^(1C), C₁-C₆ haloalkyl, or C₁-C₆ alkyl.

In certain embodiments of formula (I), R¹ is G^(1A), -G^(1B)-G^(1C), C₁-C₆ haloalkyl, or C₁-C₆ alkyl.

In certain embodiments of formula (I), R¹ is G^(1A).

In certain embodiments of formula (I), R¹ is G^(1A) wherein G^(1A) is phenyl, pyrazolyl, pyridinyl, pyrimidinyl, pyrazinyl, pyridazinyl, azetidinyl, oxetanyl, tetrahydrofuranyl, pyrrolidinyl, dihydropyridinyl, dihydropyranyl, tetrahydropyranyl, tetrahydrothienyl, piperidinyl, 1,3-benzodioxolyl, bicyclo[4.2.0]octa-1,3,5-trien-3-yl, cyclopropyl, cyclobutyl, cyclopentyl, or cyclohexyl.

In certain embodiments of formula (I), R¹ is G^(1A) wherein G^(1A) is phenyl, pyrazolyl, pyridinyl, tetrahydrofuranyl, pyrrolidinyl, tetrahydropyranyl, tetrahydrothienyl, piperidinyl, cyclopropyl, cyclopentyl, or cyclohexyl.

In certain embodiments of formula (I), R¹ is G^(1A) wherein G^(1A) is phenyl, pyridinyl, or cyclohexyl.

In certain embodiments of formula (I), R¹ is G^(1A) wherein G^(1A) is 4-7 membered monocyclic heterocycle. In some such embodiments, the 4-7 membered monocyclic heterocycle is pyrrolidinyl, piperidinyl, tetrahydrofuranyl, or tetrahydropyranyl. In some such embodiments, the 4-7 membered monocyclic heterocycle is tetrahydrofuranyl or tetrahydropyranyl.

In certain embodiments of formula (I), R¹ is G^(1A) wherein G^(1A) is C₃-C₆ monocyclic cycloalkyl. In some such embodiments, the C₃-C₆ monocyclic cycloalkyl is cyclopropyl, cyclopentyl, or cyclohexyl. In some such embodiments, the C₃-C₆ monocyclic cycloalkyl is cyclopentyl or cyclohexyl. In some such embodiments, the C₃-C₆ monocyclic cycloalkyl is cyclohexyl. In some such embodiments, the C₃-C₆ monocyclic cycloalkyl is cyclopropyl. In some such embodiments, the C₃-C₆ monocyclic cycloalkyl is cyclopentyl.

In certain embodiments of formula (I), R¹ is G^(1A) wherein G^(1A) is phenyl or 5-6 membered monocyclic heteroaryl. In some such embodiments, the 5-6 membered monocyclic heteroaryl is pyrazolyl, pyridazinyl, pyrimidinyl, or pyridinyl. In some such embodiments, the 5-6 membered monocyclic heteroaryl is pyrazolyl or pyridinyl. In some such embodiments, the 5-6 membered monocyclic heteroaryl is pyridinyl.

In certain embodiments of formula (I), R¹ is G^(1A) wherein G^(1A) is phenyl.

In certain embodiments of formula (I), R¹ is G^(1A) wherein G^(1A) is 5-6 membered monocyclic heteroaryl. In some such embodiments, the 5-6 membered monocyclic heteroaryl is pyrazolyl, pyridazinyl, pyrimidinyl, or pyridinyl. In some such embodiments, the 5-6 membered monocyclic heteroaryl is pyrazolyl or pyridinyl. In some such embodiments, the 5-6 membered monocyclic heteroaryl is pyridinyl.

In certain embodiments, G^(1A), including the exemplary rings, are optionally substituted with 1, 2, 3, or 4 independently selected R^(1a) groups.

In certain embodiments, G^(1A), including the exemplary rings, are optionally substituted with 1, 2, or 3 independently selected R^(1a) groups.

In certain embodiments, G^(1A), including the exemplary rings, are optionally substituted with 1 or 2 independently selected R^(1a) groups.

In certain embodiments, G^(1A), including the exemplary rings, are unsubstituted.

In certain embodiments, each R^(1a) is independently C₁-C₆ alkyl, halogen, C₁-C₆ haloalkyl, oxo, —CN, —S(O)₂R^(m), —S(O)₂N(R^(m))₂, —C(O)R^(m), —C(O)OR^(m), —C(O)N(R^(m))₂, —N(R^(m))₂, —N(R^(m))(alkoxyalkyl), —N(alkoxyalkyl)₂, or —(C₁-C₆ alkylenyl-CN).

In certain embodiments, each R^(1a) is independently C₁-C₆ alkyl, halogen, C₁-C₆ haloalkyl, —CN, —OR^(m), —N(R^(m))₂, —N(R^(m))(alkoxyalkyl), or —N(alkoxyalkyl)₂.

In certain embodiments, each R^(1a) is independently C₁-C₃ alkyl, halogen, C₁-C₃ haloalkyl, —CN, —OR^(m), or —N(R^(m))₂.

In certain embodiments of formula (I), R¹ is -G^(1B)-G^(1C).

In certain embodiments of formula (I), G^(m) is phenyl, pyridinyl, pyrimidinyl, pyrazinyl, or pyridazinyl.

In certain embodiments of formula (I), G^(m) is phenyl, pyridinyl, or pyrimidinyl.

In certain embodiments of formula (I), G^(1B) is phenyl or pyridinyl.

In certain embodiments of formula (I), G^(1B) is phenyl.

In certain embodiments of formula (I), G^(1C) is azetidinyl, pyrrolidinyl, piperidinyl, or morpholinyl.

In certain embodiments of formula (I), G^(1B), including the exemplary rings, are optionally substituted with 1, 2, or 3 independently selected R^(1b) groups.

In certain embodiments of formula (I), G^(1B), including the exemplary rings, are optionally substituted with 1 or 2 independently selected R^(1b) groups.

In certain embodiments of formula (I), G^(1B), including the exemplary rings, are unsubstituted.

In certain embodiments, each R^(1b) is independently C₁-C₆ alkyl, halogen, C₁-C₆ haloalkyl, or —OR^(m).

In certain embodiments of formula (I), G^(1C), including the exemplary rings, are optionally substituted with 1, 2, or 3 independently selected R^(1c) groups.

In certain embodiments of formula (I), G^(m), including the exemplary rings, are optionally substituted with 1 or 2 independently selected R^(1c) groups.

In certain embodiments of formula (I), G^(1C), including the exemplary rings, are unsubstituted.

In certain embodiments, each R^(1c) is independently C₁-C₆ alkyl, halogen, C₁-C₆ haloalkyl, or —OR^(m).

In certain embodiments of formula (I), R¹ is C₁-C₆ alkyl. In some such embodiments, R¹ is —C(CH₃)₃, —C(H)(CH₃)₂, or —CH₂—CH(CH₃)₂. In some such embodiments, R¹ is —C(H)(CH₃)₂, or —CH₂—CH(CH₃)₂. In some such embodiments, R¹ is —CH₂—CH(CH₃)₂.

In certain embodiments of formula (I), R¹ is -G^(1B)-L^(1A)-G^(1C). In some such embodiments, G^(1B) is optionally substituted 5-6 membered heteroaryl. In some such embodiments, G^(1B) is optionally substituted pyridinyl.

In certain embodiments of formula (I), R¹ is —(C₁-C₆ alkylenyl)-G^(1D). In some such embodiments, G^(1D) is optionally substituted C₃-C₆ monocyclic cycloalkyl. In some such embodiments, G^(1D) is optionally substituted cyclobutyl. In some such embodiments, G^(1D) is unsubstituted cyclobutyl. In some such embodiments, the optional substituents of G^(1D) are independently C₁-C₆ alkyl, halogen, C₁-C₆ haloalkyl, or —OR^(m).

In certain embodiments of formula (I), R² is C₂-C₄ alkenyl, C₁-C₆ alkyl, C₁-C₆ haloalkyl, —OR^(2xa), or G^(2A).

In certain embodiments of formula (I), R² is C₁-C₆ alkyl, C₁-C₆ haloalkyl, —OR^(2xa), or G^(2A).

In certain embodiments of formula (I), R² is —OR^(2xa) or G^(2A).

In certain embodiments of formula (I), R² is C₁-C₆ alkyl, C₁-C₆ haloalkyl, or G^(2A).

In certain embodiments of formula (I), R² is C₁-C₆ alkyl or G^(2A).

In certain embodiments of formula (I), R² is —CH₃, —C(H)(CH₃)₂, —C(CH₃)₃, or G^(2A).

In certain embodiments of formula (I), R² is —CH₃, —C(H)(CH₃)₂, or G^(2A).

In certain embodiments of formula (I), R² is —C(H)(CH₃)₂ or G^(2A).

In certain embodiments of formula (I), R² is C₁-C₆ alkyl.

In certain embodiments of formula (I), R² is —CH₃, —C(H)(CH₃)₂, or —C(CH₃)₃.

In certain embodiments of formula (I), R² is —CH₃ or —C(H)(CH₃)₂.

In certain embodiments of formula (I), R² is G^(2A).

In certain embodiments, G^(2A) is a C₃-C₆ monocyclic cycloalkyl. In some such embodiments, G^(2A) is cyclopropyl or cyclobutyl. In some such embodiments, G^(2A) is cyclobutyl.

In certain embodiments, G^(2A) is a 4-7 membered monocyclic heterocycle. In some such embodiments, G^(2A) is azetidinyl, oxetanyl, pyrrolidinyl, or tetrahydrofuranyl. In some such embodiments, G^(2A) is azetidinyl or oxetanyl. In some such embodiments, G^(2A) is azetidinyl.

In certain embodiments of formula (I), G^(2A) is azetidinyl, oxetanyl, pyrrolidinyl, tetrahydrofuranyl, cyclopropyl, or cyclobutyl.

In certain embodiments, G^(2A) is azetidinyl, pyrrolidinyl, cyclopropyl, or cyclobutyl.

In certain embodiments, G^(2A) is azetidinyl or cyclobutyl.

In certain embodiments, G^(2A) is azetidinyl.

In certain embodiments, G^(2A) is cyclobutyl.

In certain embodiments of formula (I), G^(2A), including the exemplary rings, are optionally substituted with 1, 2, or 3 independently selected R^(2a) groups.

In certain embodiments of formula (I), G^(2A), including the exemplary rings, are optionally substituted with 1 or 2 independently selected R^(2a) groups.

In certain embodiments of formula (I), G^(2A), including the exemplary rings, are unsubstituted.

In certain embodiments of formula (I), R² is —OR^(2xa).

In certain embodiments of formula (I), R² is —OR^(2xa) wherein R^(2xa) C₁-C₆ alkyl or G^(2B).

In certain embodiments of formula (I), R² is —OR^(2xa) wherein R^(2xa) G^(2B).

In certain embodiments of formula (I), G^(2B) is a 4-7 membered monocyclic heterocycle.

In certain embodiments of formula (I), G^(2B) is azetidinyl, oxetanyl, pyrrolidinyl, piperidinyl, tetrahydrofuranyl, or tetrahydropyranyl.

In certain embodiments of formula (I), G^(2B) is azetidinyl, oxetanyl, pyrrolidinyl, piperidinyl, or tetrahydrofuranyl.

In certain embodiments of formula (I), G^(2B) is azetidinyl or oxetanyl.

In certain embodiments of formula (I), G^(2B) is azetidinyl.

In certain embodiments of formula (I), G^(2B) is oxetanyl.

In certain embodiments of formula (I), G^(2B) is a C₃-C₆ monocyclic cycloalkyl.

In certain embodiments of formula (I), G^(2B) is cyclobutyl.

In certain embodiments, G^(2B), including the exemplary rings, are optionally substituted with 1, 2, or 3 independently selected R^(2a) groups.

In certain embodiments, G^(2B), including the exemplary rings, are optionally substituted with 1 or 2 independently selected R^(2a) groups.

In certain embodiments, G^(2B), including the exemplary rings, are unsubstituted.

In certain embodiments of formula (I), each R^(2a) is independently C₁-C₆ alkyl, halogen, C₁-C₆ haloalkyl, oxo, —CN, —C(O)R^(m), —C(O)OR^(m), or —(C₁-C₆ alkylenyl-CN).

In certain embodiments of formula (I), each R^(2a) is independently C₁-C₃ alkyl, halogen, C₁-C₃ haloalkyl, —OR^(m), or —C(O)OR^(m).

In certain embodiments of formula (I), R² is —(C₁-C₆ alkylenyl)-OR^(2xb), —(C₁-C₆ alkylenyl)-N(R^(2xb))₂, —C(O)OR^(2xb), or —C(O)N(R^(2xb))₂.

In certain embodiments of formula (I), R³ is G^(3A), -G^(3B)-L¹-G^(3C), -G^(3B)-L³-G^(3C)-L⁴-G^(3F), —(C₁-C₆ alkylenyl)-G^(3E), —OR^(3a), or —N(R^(3a))(R^(3b)).

In certain embodiments of formula (I), R³ is G^(3A), -G^(3B)-L¹-G^(3C), —OR^(3a), or —N(R^(3a))(R^(3b)).

In certain embodiments of formula (I), R³ is G^(3A), -G^(3B)-L¹-G^(3C), or —OR^(3a).

In certain embodiments of formula (I), R³ is G^(3A) or -G^(3B)-L¹-G^(3C).

In certain embodiments of formula (I), R³ is G^(3A).

In certain embodiments of formula (I), R³ is G^(3A) wherein G^(3A) is phenyl, 5-6 membered monocyclic heteroaryl, or 4-11 membered heterocycle.

In certain embodiments of formula (I), R³ is G^(3A) wherein G^(3A) is phenyl or 5-6 membered monocyclic heteroaryl.

In certain embodiments of formula (I), R³ is G^(3A) wherein G^(3A) is phenyl, pyrazolyl, pyrrolyl, pyridinyl, pyrimidinyl, pyridazinyl, or pyrazinyl.

In certain embodiments of formula (I), R³ is G^(3A) wherein G^(3A) is phenyl, pyridinyl, pyrimidinyl, pyridazinyl, or pyrazinyl.

In certain embodiments of formula (I), R³ is G^(3A) wherein G^(3A) is phenyl, pyridinyl, or pyrimidinyl.

In certain embodiments of formula (I), R³ is G^(3A) wherein G^(3A) is phenyl.

In certain embodiments of formula (I), R³ is G^(3A) wherein G^(3A) is pyridinyl.

In certain embodiments of formula (I), R³ is G^(3A) wherein G^(3A) is a 4-11 membered heterocycle.

In certain embodiments of formula (I), R³ is G^(3A) wherein G^(3A) is azetidinyl, pyrrolidinyl, piperidinyl, dihydropyranyl, piperazinyl, morpholinyl, thiomorpholinyl, tetrahydropyridinyl, azepanyl, 1,4-oxazepanyl, 1,4-diazepanyl, 2-azaspiro[3.3]heptyl, 2-oxaspiro[3.3]heptyl, 5-azaspiro[2.4]heptyl, 2-azaspiro[3.4]octyl, 5-azaspiro[2.5]octyl, 5-azaspiro[3.4]octyl, 5-oxa-2-azaspiro[3.5]nonyl, 6-oxa-2-azaspiro[3.4]octyl, 6-oxa-2-azaspiro[3.5]nonyl, 7-oxa-2-azaspiro[3.5]nonyl, 1-oxa-7-azaspiro[3.5]nonyl, 1-oxa-7-azaspiro[4.4]nonyl, 1,4-dioxa-7-azaspiro[4.4]nonyl, 2-oxa-7-azaspiro[3.5]nonyl, 7-azaspiro[3.5]nonyl, 2,7-diazaspiro[4.4]nonyl, 2-azaspiro[3.5]nonyl, 1,3,8-triazaspiro[4.5]decyl, 8-azaspiro[4.5]decyl, 8-oxa-2-azaspiro[4.5]decyl, 1-oxa-8-azaspiro[4.5]decyl, 1-oxa-3,8-diazaspiro[4.5]decyl, 1-oxa-4,9-diazaspiro[5.5]undecyl, 1,4-dioxa-8-azaspiro[4.5]decyl, 3-azaspiro[5.5]undecyl, 3-azabicyclo[3.1.0]hexyl, 8-azabicyclo[3.2.1]octyl, 3,9-diazaspiro[5.5]undecyl, 2,8-diazaspiro[4.5]decyl, octahydropyrrolo[3,4-c]pyrrolyl, hexahydro-1H-oxazolo[3,4-a]pyrazinyl, octahydropyrrolo[1,2-a]pyrazinyl, octahydroimidazo[1,5-a]pyrazinyl, octahydro-1H-pyrrolo[3,2-c]pyridinyl, hexahydropyrrolo[3,4-b][1,4]oxazin-6(2H)-yl, octahydropyrrolo[3,4-b]azepin-7(1H)-yl, or isoindolinyl.

In certain embodiments of formula (I), R³ is G^(3A) wherein G^(3A) is a 4-7 membered monocyclic heterocycle.

In certain embodiments of formula (I), R³ is G^(3A) wherein G^(3A) is azetidinyl, pyrrolidinyl, piperidinyl, dihydropyranyl, piperazinyl, morpholinyl, thiomorpholinyl, tetrahydropyridinyl, azepanyl, 1,4-oxazepanyl, or 1,4-diazepanyl.

In certain embodiments of formula (I), R³ is G^(3A) wherein G^(3A) is azetidinyl, piperidinyl, or piperazinyl.

In certain embodiments of formula (I), R³ is G^(3A) wherein G^(3A) is piperidinyl or piperazinyl.

In certain embodiments of formula (I), R³ is G^(3A) wherein G^(3A) is piperidinyl.

In certain embodiments, each of the aforementioned G^(3A), including the exemplary rings, are optionally substituted with 1, 2, 3, or 4 independently selected R^(e) groups.

In certain embodiments, each of the aforementioned G^(3A), including the exemplary rings, are optionally substituted with 1, 2, or 3 independently selected R^(e) groups.

In certain embodiments, each of the aforementioned G^(3A), including the exemplary rings, are optionally substituted with 1 or 2 independently selected R^(e) groups.

In certain embodiments, G^(3A), including the exemplary rings, are unsubstituted.

In certain embodiments, each of the optional substituents of G^(3A) is independently C₁-C₆ alkyl, C₁-C₆ haloalkyl, halogen, oxo, —CN, —N₃, —OR^(f), —S(O)₂R^(f), —C(O)R^(f), —C(O)OR^(f), —C(O)NR^(f)R^(h), —N(R^(f))₂, —N(R^(h))C(O)R^(h), —N(R^(h))S(O)₂R^(g), or —N(R^(h))C(O)O(R^(g)); wherein the C₁-C₆ haloalkyl and the C₁-C₆ alkyl are each optionally substituted with 1 or 2 substituents independently selected from the group consisting of —CN, —OR^(f), —N(R^(f))₂, —C(O)N(R^(f))₂, and —N(R^(h))C(O)O(R^(g)).

In certain embodiments, each of the optional substituents of G^(3A) is independently C₁-C₆ alkyl, C₁-C₆ haloalkyl, halogen, oxo, —CN, —N₃, —OR^(f), —S(O)₂R^(f), —C(O)OR^(f), —N(R^(f))₂, or —N(R^(h))C(O)R^(h); wherein the C₁-C₆ haloalkyl and the C₁-C₆ alkyl are each optionally substituted with 1 or 2 substituents independently selected from the group consisting of —CN, —OR^(f), and —N(R^(f))₂; and each R^(f) is independently hydrogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, —(C₁-C₆ alkylenyl)-OR^(m), or —(C₁-C₆ alkylenyl)-N(R^(m))₂.

In certain embodiments, each of the optional substituents of G^(3A) is independently C₁-C₆ alkyl, C₁-C₆ haloalkyl, halogen, —CN, —OR^(f), or —N(R^(f))₂; wherein the C₁-C₆ haloalkyl and the C₁-C₆ alkyl are each optionally substituted with 1 or 2 substituents independently selected from the group consisting of —OR^(f) and —N(R^(f))₂; and each R^(f) is independently hydrogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, —(C₁-C₆ alkylenyl)-OR^(m), or —(C₁-C₆ alkylenyl)-N(R^(m))₂.

In certain embodiments of formula (I), R³ is -G^(3B)-L¹-G^(3C).

In certain embodiments of formula (I), R³ is -G^(3B)-L³-G^(3C)-L⁴-G^(3F) or —(C₁-C₆ alkylenyl)-G^(3E).

In certain embodiments of formula (I), G^(3B) is phenyl, 5-6 membered monocyclic heteroaryl, or 4-7 membered monocyclic heterocycle.

In certain embodiments of formula (I), G^(3B) is phenyl, pyridinyl, pyrazinyl, pyrimidinyl, pyridazinyl, azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl, morpholinyl, 1,4-diazepanyl, octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl, 1-oxa-8-azaspiro[4.5]decyl, or 3,9-diazaspiro[5.5]undecyl.

In certain embodiments of formula (I), G^(3B) is phenyl, pyridinyl, pyrimidinyl, azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl, or 1,4-diazepanyl.

In certain embodiments of formula (I), G^(3B) is a 4-7 membered monocyclic heterocycle.

In certain embodiments of formula (I), G^(3B) is azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl, morpholinyl, or 1,4-diazepanyl.

In certain embodiments of formula (I), G^(3B) is piperidinyl or piperazinyl.

In certain embodiments of formula (I), G^(3B) is piperidinyl.

In certain embodiments of formula (I), G^(3B) is piperazinyl.

In certain embodiments of formula (I), G^(3C) is C₃-C₆ monocyclic cycloalkyl, phenyl, 5-6 membered monocyclic heteroaryl, or 4-11 membered heterocycle.

In certain embodiment of formula (I)s, G^(3C) is cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, phenyl, pyridinyl, pyrazinyl, pyrimidinyl, pyridazinyl, azetidinyl, oxetanyl, pyrrolidinyl, tetrahydrofuranyl, 1,3-dioxolanyl, 1,4-diazepanyl, 1,4-oxazepanyl, oxazolidinyl, piperidinyl, piperazinyl, tetrahydropyranyl, thiomorpholinyl, morpholinyl, 2-oxa-5-azabicyclo[2.2.1]heptyl, 3-azabicyclo[3.1.0]hexyl, hexahydropyrrolo[1,2-a]pyrazin-2(1H)-yl, 2-oxa-6-azaspiro[3.3]heptyl, 6-oxa-2-azaspiro[3.5]nonyl, 2-oxa-5,8-diazaspiro[3.5]nonyl, 6-oxa-2-azaspiro[3.4]octyl, 2-oxa-6-azaspiro[3.4]octyl, 8-oxa-3-azabiclo[3.2.1]octyl, or 2-oxa-7-azaspiro[3.5]nonyl.

In certain embodiments of formula (I), G^(3C) is a 4-7 membered monocyclic heterocycle.

In certain embodiments of formula (I), G^(3C) is azetidinyl, oxetanyl, pyrrolidinyl, tetrahydrofuranyl, oxazolidinyl, piperidinyl, piperazinyl, tetrahydropyranyl, thiomorpholinyl, or morpholinyl.

In certain embodiments of formula (I), G^(3C) is azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl, tetrahydropyranyl, tetrahydropyranyl, or morpholinyl.

In certain embodiments of formula (I), G^(3C) is pyrrolidinyl, piperidinyl, piperazinyl, or morpholinyl.

In certain embodiments, each of the aforementioned G^(3B) and G^(3C), including the exemplary rings, are optionally substituted with 1, 2, 3, or 4 independently selected R^(e) groups.

In certain embodiments, each of the aforementioned G^(3B) and G^(3C), including the exemplary rings, are optionally substituted with 1, 2, or 3 independently selected R^(e) groups.

In certain embodiments, each of the aforementioned G^(3B) and G^(3C), including the exemplary rings, are optionally substituted with 1 or 2 independently selected R^(e) groups.

In certain embodiments, G^(3B) and G^(3C), including the exemplary rings, are unsubstituted.

In certain embodiments, each of the optional substituents of G^(3B) is independently C₁-C₆ alkyl, C₁-C₆ haloalkyl, halogen, —OR^(f), or —CN. In some such embodiments, R^(f) is hydrogen, C₁-C₃ alkyl, or C₁-C₃ haloalkyl.

In certain embodiments, each of the optional substituents of G^(3B) is independently —CH₃, —CH₂F, —CHF₂, —CF₃, or F.

In certain embodiments, each of the optional substituents of G^(3C) is independently C₁-C₆ alkyl, C₁-C₆ haloalkyl, halogen, oxo, or —CN.

In certain embodiments, each of the optional substituents of G^(3C) is independently —CH₃, —C(CH₃)₃, —CH₂F, —CHF₂, —CF₃, —CH₂CH₂CF₃, F, or —CN.

In certain embodiments, L¹ is a bond, C₁-C₃ alkylenyl, or (C₁-C₃ alkylenyl)_(r)-L²-(C₁-C₃ alkylenyl)_(s).

In certain embodiments, L¹ is a bond.

In certain embodiments, L¹ is C₁-C₃ alkylenyl.

In certain embodiments, L² is O, N(R^(x)), or C(O).

In certain embodiments, L² is O or N(R^(x)).

In certain embodiments of formula (I), R³ is —OR^(3a).

In certain embodiments of formula (I), R³ is —OR^(3a) wherein R^(3a) is G^(3E), C₁-C₆ haloalkyl, or C₁-C₆ alkyl; wherein the C₁-C₆ haloalkyl and the C₁-C₆ alkyl are each substituted with one or two substituents independently selected from the group consisting of G^(3E), —OR^(3xa), —C(O)G^(3D), —N(R^(3xb))₂, and —S(O)₂R^(3xc).

In certain embodiments of formula (I), R³ is —OR^(3a) wherein R^(3a) is G^(3E).

In certain embodiments of formula (I), R³ is —OR^(3a) wherein R^(3a) is C₁-C₆ haloalkyl or C₁-C₆ alkyl; wherein the C₁-C₆ haloalkyl and the C₁-C₆ alkyl are each substituted with one substituent selected from the group consisting of —OR³″ and —NR^(3xb))₂.

In certain embodiments of formula (I), R³ is —OR^(3a) wherein R^(3a) is C₁-C₆ haloalkyl or C₁-C₆ alkyl; wherein the C₁-C₆ haloalkyl and the C₁-C₆ alkyl are each substituted with one G^(3E).

In certain embodiments, G^(3E) is azetidinyl, oxetanyl, pyrrolidinyl, tetrahydrofuranyl, imidazolidinyl, tetrahydropyranyl, piperidinyl, piperazinyl, thiomorpholinyl, morpholinyl, 1,3-dioxolanyl, azepanyl, 1,4-diazepanyl, 1,3-dioxanyl, 1,4-dioxanyl, 2-oxaspiro[3.3heptyl, 8-azaspiro[4.5]decyl, 5-azaspiro[3.4]octyl, 8-azabicyclo[3.2.1]octyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, or cyclooctyl.

In certain embodiments, G^(3E) is a 4-11 membered heterocycle.

In certain embodiments, G^(3E) is oxetanyl, pyrrolidinyl, tetrahydrofuranyl, imidazolidinyl, tetrahydropyranyl, piperidinyl, piperazinyl, thiomorpholinyl, morpholinyl, 1,3-dioxolanyl, azepanyl, 1,4-diazepanyl, 1,3-dioxanyl, 1,4-dioxanyl, or 8-azaspiro[4.5]decyl.

In certain embodiments, G^(3E) is a 4-7 membered monocyclic heterocycle.

In certain embodiments, G^(3E) is oxetanyl, pyrrolidinyl, tetrahydrofuranyl, imidazolidinyl, tetrahydropyranyl, piperidinyl, piperazinyl, thiomorpholinyl, morpholinyl, 1,3-dioxolanyl, azepanyl, 1,4-diazepanyl, 1,3-dioxanyl, or 1,4-dioxanyl.

In certain embodiments, G^(3E) is tetrahydrofuranyl, tetrahydropyranyl, piperidinyl, piperazinyl, thiomorpholinyl, morpholinyl, or 1,4-dioxanyl.

In certain embodiments, G^(3E) is piperidinyl, piperazinyl, tetrahydropyranyl, or morpholinyl.

In certain embodiments, G^(3E) is tetrahydropyranyl.

In certain embodiments, each of the aforementioned G^(3E), including the exemplary rings, is optionally substituted with 1, 2, 3, or 4 independently selected R^(e) groups.

In certain embodiments, each of the aforementioned G^(3E), including the exemplary rings, is optionally substituted with 1, 2, or 3 independently selected R^(e) groups.

In certain embodiments, each of the aforementioned G^(3E), including the exemplary rings, is optionally substituted with 1 or 2 independently selected R^(e) groups.

In certain embodiments, G^(3E), including the exemplary rings, is unsubstituted.

In certain embodiments, each of the aforementioned G^(3E), including the exemplary rings, is substituted with one G^(3F); and said G^(3E) is optionally further substituted with 1 or 2 independently selected R^(e) groups. In some such embodiments, G^(3F) is azetidinyl, oxetanyl, thiomorpholinyl, piperidinyl, or cyclohexyl.

In certain embodiments, each of the optional substituents of G^(3E) is independently C₁-C₆ alkyl or C₁-C₆ haloalkyl, wherein the C₁-C₆ alkyl and C₁-C₆ haloalkyl are each optionally substituted with 1 or 2 substituents independently selected from the group consisting of —CN, —OR^(f), and —N(R^(f))₂.

In certain embodiments of formula (I), R³ is —N(R^(3a))(R^(3b)).

In certain embodiments of formula (I), R³ is —N(R^(3a))(R^(3b)) wherein R^(1a) is G^(3E), C₁-C₃ haloalkyl, or C₁-C₃ alkyl; wherein the C₁-C₃ haloalkyl and the C₁-C₃ alkyl are each substituted with one substituent independently selected from the group consisting of G^(3E), —OR^(3xa) and —N(R^(3xb))₂. In some such embodiments, R^(3xa), at each occurrence, is independently hydrogen, C₁-C₃ haloalkyl, or C₁-C₃ alkyl; and R^(3xb), at each occurrence, is independently hydrogen, C₁-C₃ haloalkyl, C₁-C₃ alkyl; and G^(3E). In some such embodiments, G^(3E) is optionally substituted C₃-C₆ monocyclic cycloalkyl or optionally substituted 4-7 membered monocyclic heterocycle. In some such embodiments, G^(3E) is cyclobutyl, tetrahydrofuranyl, tetrahydropyranyl, piperidinyl, or morpholinyl.

In certain embodiments of formula (I), R³ is -G^(3B)-L³-G^(3C)-L⁴-G^(3F).

In certain embodiments of formula (I), R³ is -G^(3B)-L³-G^(3C)-L⁴-G^(3F) wherein L⁴ is a bond, C₁-C₆ alkylenyl, N(R^(2x)), or C(O). In some such embodiments, G^(3B) is phenyl, 5-6 membered monocyclic heteroaryl, or 4-7 membered monocyclic heterocycle, each of which is optionally substituted; and G^(3C) is optionally substituted 4-7 membered monocyclic heterocycle.

In certain embodiments of formula (I), R³ is —(C₁-C₆ alkylenyl)-G^(3E).

In certain embodiments of formula (I), R³ is —N(R^(3b))C(O)G^(3D) or —C(O)G^(3D).

In certain embodiments of formula (I), R⁴ is hydrogen or C₁-C₃ alkyl.

In certain embodiments of formula (I), R⁴ is hydrogen.

Various embodiments of substituents R¹, R², R³, R⁴, G^(1A), R^(1a), G^(1B), G^(1C), R^(1b), R^(1c), G^(1D), R^(1d), G^(2A), G^(2B), R^(2a), R^(2xa), G^(3A), G^(3B), G^(3C), G^(3D), G^(3E), R^(e), R^(f), L¹, L², L^(1A), L³, L⁴, R^(3a), and R^(3b) have been discussed above. These substituents embodiments can be combined to form various embodiments of the invention. All embodiments of present compounds, formed by combining the substituent embodiments discussed above are within the scope of Applicant's invention, and some illustrative embodiments of present compounds are provided below.

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A) or -G^(1B)-G^(1C); and R² is C₂-C₄ alkenyl, C₁-C₆ alkyl, C₁-C₆ haloalkyl, —OR^(2xa), or G^(2A).

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A) or -G^(1B)-G^(1C); and R³ is G^(3A), -G^(3B)-L¹-G^(3C), —OR^(3a), or —N(R^(3a))(R^(3b)).

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A) or -G^(1B)-G^(1C); R² is C₂-C₄ alkenyl, C₁-C₆ alkyl, C₁-C₆ haloalkyl, —OR^(2xa), or G^(2A); and R³ is G^(3A), -G^(3B)-L¹-G^(3C), —OR^(3a), —N(R^(3a))(R^(3b)).

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A) or -G^(1B)-G^(1C); G^(1A) is phenyl or 5-6 membered monocyclic heteroaryl; R² is C₁-C₆ alkyl; R³ is G^(3A), -G^(3B)-L¹-G^(3C), —OR^(3a), —N(R^(3a))(R^(3b)); and G^(3A) is a 4-11 membered heterocycle.

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A) or -G^(1B)-G^(1C); G^(1A) is phenyl or 5-6 membered monocyclic heteroaryl; R² is —OR^(2xa) or G^(2A); R^(2xa) is G^(2B); and R³ is G^(3A), -G^(3B)-L¹-G^(3C), —OR^(3a), or —N(R^(3a))(R^(3b)).

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A) or -G^(1B)-G^(1C); G^(1A) is phenyl or 5-6 membered monocyclic heteroaryl; R² is G^(2A); G^(2A) is C₃-C₆ monocyclic cycloalkyl; and R³ is G^(3A), -G^(3B)-L¹-G^(3C), —OR^(3a), —N(R^(3a))(R^(3b)).

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A) or -G^(1B)-G^(1C); R² is C₁-C₆ alkyl or G^(2A); and R³ is G^(3A), -G^(3B)-L¹-G^(3C), or —OR^(3a).

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A); G^(1A) is phenyl or 5-6 membered monocyclic heteroaryl; R² is C₁-C₆ alkyl; R³ is G^(3A); and G^(3A) is a 4-7 membered monocyclic heterocycle.

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A); G^(1A) is phenyl or 5-6 membered monocyclic heteroaryl; R² is G^(2A); G^(2A) is C₃-C₆ monocyclic cycloalkyl; R³ is G^(3A); and G^(3A) is a phenyl, 5-6 membered monocyclic heteroaryl, or 4-11 membered heterocycle.

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A); G^(1A) is phenyl or 5-6 membered monocyclic heteroaryl; R² is G^(2A); G^(2A) is C₃-C₆ monocyclic cycloalkyl; R³ is G^(3A); and G^(3A) is a 4-7 membered monocyclic heterocycle.

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A); G^(1A) is phenyl or 5-6 membered monocyclic heteroaryl; R² is C₁-C₆ alkyl or G^(2A); G^(2A) is C₃-C₆ monocyclic cycloalkyl; and R³ is -G^(3B)-L¹-G^(3C).

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A); G^(1A) is phenyl or 5-6 membered monocyclic heteroaryl; R² is C₁-C₆ alkyl or G^(2A); G^(2A) is C₃-C₆ monocyclic cycloalkyl; R³ is -G^(3B)-L¹-G^(3C); L¹ is a bond, C₁-C₃ alkylenyl, or (C₁-C₃ alkylenyl)_(r)-L²-(C₁-C₃ alkylenyl)_(s); L² is O, N(R^(x)), or C(O); and G^(3B) is phenyl, 5-6 membered monocyclic heteroaryl, or 4-7 membered monocyclic heterocycle.

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A); G^(1A) is phenyl or 5-6 membered monocyclic heteroaryl; R² is C₁-C₆ alkyl or G^(2A); G^(2A) is C₃-C₆ monocyclic cycloalkyl; R³ is -G^(3B)-L¹-G^(3C); L¹ is a bond, C₁-C₃ alkylenyl, or (C₁-C₃ alkylenyl)_(r)-L²-(C₁-C₃ alkylenyl)_(s); L² is O or N(R^(x)); and G^(3B) is 4-7 membered monocyclic heterocycle.

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A); G^(1A) is phenyl or 5-6 membered monocyclic heteroaryl; R² is C₁-C₆ alkyl or G^(2A); G^(2A) is C₃₋C₆ monocyclic cycloalkyl; R³ is —OR^(3a); and R^(3a) is G^(3E), C₁-C₆ haloalkyl, or C₁-C₆ alkyl; wherein the C₁-C₆ haloalkyl and the C₁-C₆ alkyl are each substituted with one or two substituents independently selected from the group consisting of G^(3E), —OR^(3xa), —C(O)G^(3D), —N(R^(3xb))₂, and —S(O)₂R^(3xc).

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A); G^(1A) is phenyl or 5-6 membered monocyclic heteroaryl; R² is C₁-C₆ alkyl or G^(2A); G^(2A) is C₃-C₆ monocyclic cycloalkyl; R³ is —OR^(3a); and R^(3a) is C₁-C₆ haloalkyl or C₁-C₆ alkyl; wherein the C₁-C₆ haloalkyl and the C₁-C₆ alkyl are each substituted with one G^(3E).

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A); G^(1A) is phenyl or 5-6 membered monocyclic heteroaryl; R² is C₁-C₆ alkyl or G^(2A); G^(2A) is C₃-C₆ monocyclic cycloalkyl; R³ is —OR^(3a); R^(1a) is C₁-C₆ haloalkyl or C₁-C₆ alkyl; wherein the C₁-C₆ haloalkyl and the C₁-C₆ alkyl are each substituted with one G^(3E); and G^(3E) is a 4-7 membered monocyclic heterocycle.

In one embodiment, the invention is directed to compounds wherein R¹ is -G^(1B)-G^(1C); R² is C₁-C₆ alkyl or G^(2A); and R³ is G^(3A), -G^(3B)-L¹-G^(3C), or —OR^(3a).

In one embodiment, the invention is directed to compounds wherein R¹ is -G^(1B)-G^(1C); R² is C₁-C₆ alkyl or G^(2A); R³ is G^(3A); and G^(3A) is phenyl, 5-6 membered monocyclic heteroaryl, or 4-11 membered heterocycle.

In one embodiment, the invention is directed to compounds wherein R¹ is -G^(1B)-G^(1c); R² is C₁-C₆ alkyl or G^(2A); R³ is G^(3A); and G^(3A) is 4-7 membered monocyclic heterocycle.

In one embodiment, the invention is directed to compounds wherein R¹ is -G^(1B)-G^(1C). R² is C₁-C₆ alkyl or G^(2A); R³ is -G^(3B)-L¹-G^(3C); and G^(3B) is phenyl, 5-6 membered monocyclic heteroaryl, or 4-7 membered monocyclic heterocycle.

In one embodiment, the invention is directed to compounds wherein R¹ is -G^(1B)-G^(1C); R² is C₁-C₆ alkyl or G^(2A); R³ is -G^(3B)-L¹-G^(3C); L¹ is a bond, C₁-C₃ alkylenyl, or (C₁-C₃ alkylenyl)_(r)-L²-(C₁-C₃ alkylenyl)_(s); L² is O or N(R^(x)); and G^(3B) is 4-7 membered monocyclic heterocycle.

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A) or -G^(1B)-G^(1C); R² is C₁-C₆ alkyl or G^(2A); and R³ is G^(3B)-L³-G^(3C) or —(C₁-C₆ alkylenyl)-G^(3E).

In one embodiment, the invention is directed to compounds wherein R¹ is G^(1A); G^(1A) is optionally substituted phenyl or optionally substituted 5-6 membered monocyclic heteroaryl; R² is C₁-C₆ alkyl or G^(2A) wherein G^(2A) is optionally substituted C₃-C₆ monocyclic cycloalkyl; R³ is -G^(3B)-L³-G^(3C)-L⁴-G^(3F) or —(C₁-C₆ alkylenyl)-G^(3E); and L⁴ is a bond, C₁-C₆ alkylenyl, N(R^(2x)), or C(O).

In one embodiment, the invention is directed to compounds wherein

-   -   R¹ is G^(1A), -G^(1B)-G^(1C), -G^(1B)-L^(1A)-G^(1C), C₁-C₆         haloalkyl, C₁-C₆ alkyl, —(C₁-C₆ alkylenyl)-CN, —(C₁-C₆         alkylenyl)-G^(1D), or -G^(1D)-O-benzyl;     -   G^(1A) is phenyl, aryl, 5-6 membered monocyclic heteroaryl, 4-7         membered monocyclic heterocycle, or C₃-C₆ monocyclic cycloalkyl;         wherein each G^(1A) is optionally substituted with 1, 2, 3, or 4         independently selected R^(1a) groups;     -   G^(1B) is phenyl or 5-6 membered monocyclic heteroaryl; wherein         each G^(1B) is optionally substituted with 1, 2, 3, or 4         independently selected R^(1b) groups;     -   G^(1C) is 4-7 membered monocyclic heterocycle which is         optionally substituted with 1, 2, 3, or 4 independently selected         R^(1c) groups;     -   G^(1D), at each occurrence, is a 4-7 membered monocyclic         heterocycle, or a C₃-C₆ monocyclic cycloalkyl; wherein each         G^(1D) is optionally substituted with 1, 2, 3, or 4         independently selected R^(1d) groups;     -   R² is C₂-C₄ alkenyl, C₁-C₆ alkyl, C₁-C₆ haloalkyl, —OR^(2xa),         —(C₁-C₆ alkylenyl)-OR^(2xb), —(C₁-C₆ alkylenyl)-N(R^(2xb))₂,         —C(O)OR^(2xb), —C(O)N(R^(2xb))₂, or -G^(2A);     -   R^(2xa) is hydrogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, or G^(2B);     -   R^(2xb), at each occurrence, is independently hydrogen, C₁-C₆         alkyl, or C₁-C₆ haloalkyl;     -   G^(2A) and G^(2B) are each independently 4-7 membered monocyclic         heterocycle or C₃-C₆ monocyclic cycloalkyl; wherein G^(2A) and         G^(2B) are each optionally substituted with 1, 2, or 3         independently selected R^(2a) groups;     -   R³ is G^(3A), -G^(3B)-L¹-G^(3C), —OR^(3a), —N(R^(3a))(R^(3b)),         —N(R^(3b))C(O)G^(3D), or —C(O)G^(3D);     -   R^(3a), at each occurrence, is independently G^(3E), C₁-C₆         haloalkyl, or C₁-C₆ alkyl; wherein the C₁-C₆ haloalkyl and the         C₁-C₆ alkyl are each optionally substituted with one or two         substituents independently selected from the group consisting of         G^(3E), —OR^(3xa), —C(O)G^(3D), —N(R^(3xb))₂, and —S(O)₂R^(3xc);     -   R^(3xa), R^(3xb), and R^(3xc), at each occurrence, are each         independently hydrogen, C₁-C₆ haloalkyl, C₁-C₆ alkyl, G^(3E),         —(C₁-C₆ alkylenyl)-OR^(3ya), or —(C₁-C₆ alkylenyl)-N(R^(3ya))₂;         wherein R^(3ya), at each occurrence, is independently hydrogen,         C₁-C₆ alkyl, or C₁-C₆ haloalkyl;     -   R^(3b), at each occurrence, is hydrogen, C₁-C₆ alkyl, or C₁-C₆         haloalkyl;     -   L¹ is a bond, C₁-C₆ alkylenyl, (C₁-C₆ alkylenyl)_(r)-L²-(C₁-C₆         alkylenyl)_(s), or O—(C₁-C₆ alkylenyl)-C(O), wherein the left         end of the L¹ moiety is attached to G^(3B);     -   L² is O, N(R^(x)), C(O), N(R^(x))C(O), or C(O)N(R^(x)); wherein         each R^(x) is independently hydrogen, C₁-C₆ alkyl, or C₁-C₆         haloalkyl;     -   r is 0 or 1;     -   s is 0 or 1;     -   G^(3A), G^(3B), and G^(3C), are each independently C₃-C₁₁         cycloalkyl, phenyl, 5-6 membered monocyclic heteroaryl, or 4-11         membered heterocycle, wherein G^(3A), G^(3B), and G^(3C) are         each optionally substituted with 1, 2, 3, or 4 independently         selected R^(e) groups;     -   G^(3D), at each occurrence, is 4-7 membered monocyclic         heterocycle which is optionally substituted with 1, 2, 3, or 4         independently selected R^(e) groups;     -   G^(3E), at each occurrence, is independently C₃-C₈ monocyclic         cycloalkyl or 4-11 membered heterocycle; wherein each G^(3E) is         optionally substituted with 1, 2, 3, or 4 substituents         independently selected from the group consisting of R^(e) and         G^(3F);     -   G^(3F), at each occurrence, is independently a 4-7 membered         monocyclic heterocycle or a C₃-C₆ monocyclic cycloalkyl; wherein         each G^(3F) is optionally substituted with 1, 2, 3, or 4         independently selected R^(e) groups;     -   R^(e), at each occurrence, is independently C₂-C₆ alkenyl, C₂-C₆         alkynyl, C₁-C₆ alkyl, C₁-C₆ haloalkyl, halogen, oxo, —CN, —N₃,         NO₂, —OR^(f), —OC(O)R^(g), —OC(O)NR^(f)R^(h), —SR^(f),         —S(O)₂R^(f), —S(O)₂NR^(f)R^(h), —C(O)R^(f), —C(O)OR^(f),         —C(O)NR^(f)R^(h), —C(O)N(R^(h))S(O)₂R^(f), —N(R^(f))₂,         —N(R^(h))C(O)R^(f), —N(R^(h))S(O)₂R^(g), —N(R^(h))C(O)O(R^(g)),         —N(R^(h))C(O)NR^(f)R^(h), or —N(R^(h))S(O)₂NR^(f)R^(h); wherein         the C₁-C₆ haloalkyl and the C₁-C₆ alkyl are each optionally         substituted with 1 or 2 substituents independently selected from         the group consisting of halogen, —CN, NO₂, —OR^(f), —OC(O)R^(g),         —OC(O)NR^(f)R^(h), —SR^(f), —S(O)₂R^(f), —S(O)₂NR^(f)R^(h),         —C(O)R, —C(O)OR, —C(O)NR^(f)R^(h), —C(O)N(R^(h))S(O)₂R^(f),         —N(R^(f))₂, —N(R^(h))C(O)R^(f), —N(R^(h))S(O)₂R^(g),         —N(R^(h))C(O)O(R^(g)), —N(R^(h))C(O)NR^(f)R^(h), and         —N(R^(h))S(O)₂NR^(f)R^(h);     -   R^(f), at each occurrence, is independently hydrogen, C₁-C₆         alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₁-C₆ haloalkyl, —(C₁-C₆         alkylenyl)-CN, —(C₁-C₆ alkylenyl)-OR^(m), —(C₁-C₆         alkylenyl)-OC(O)R^(n), —(C₁-C₆ alkylenyl)-OC(O)N(R^(m))₂,         —(C₁-C₆ alkylenyl)-SR^(m), —(C₁-C₆ alkylenyl)-S(O)₂R^(m),         —(C₁-C₆ alkylenyl)-S(O)₂N(R^(m))₂, —(C₁-C₆ alkylenyl)-C(O)R^(m),         —(C₁-C₆ alkylenyl)-C(O)OR^(m), —(C₁-C₆ alkylenyl)-C(O)N(R^(m))₂,         —(C₁-C₆ alkylenyl)-C(O)N(R^(m))S(O)₂R^(n), —(C₁-C₆         alkylenyl)-N(R^(m))₂, —(C₁-C₆ alkylenyl)-N(R^(m))C(O)R^(n),         —(C₁-C₆ alkylenyl)-N(R^(m))S(O)₂R^(n), —(C₁-C₆         alkylenyl)-N(R^(m))C(O)O(R^(n)), —(C₁-C₆         alkylenyl)-N(R^(m))C(O)N(R^(m))₂, or —(C₁-C₆         alkylenyl)-N(R^(m))S(O)₂N(R^(m))₂;     -   R^(g), at each occurrence, is independently C₁-C₆ alkyl, C₂-C₆         alkenyl, C₂-C₆ alkynyl, C₁-C₆ haloalkyl, —(C₁-C₆ alkylenyl)-CN,         —(C₁-C₆ alkylenyl)-OR^(m), —(C₁-C₆ alkylenyl)-OC(O)R^(n),         —(C₁-C₆ alkylenyl)-OC(O)N(R^(m))₂, —(C₁-C₆ alkylenyl)-SR^(m),         —(C₁-C₆ alkylenyl)-S(O)₂R^(m), —(C₁-C₆         alkylenyl)-S(O)₂N(R^(m))₂, alkylenyl)-C(O)R^(m), —(C₁-C₆         alkylenyl)-C(O)OR^(m), —(C₁-C₆ alkylenyl)-C(O)N(R^(m))₂, —(C₁-C₆         alkylenyl)-C(O)N(R^(m))S(O)₂R^(n), —(C₁-C₆ alkylenyl)-N(R^(m))₂,         —(C₁-C₆ alkylenyl)-N(R^(m))C(O)R^(n), —(C₁-C₆         alkylenyl)-N(R^(m))S(O)₂R^(n), —(C₁-C₆         alkylenyl)-N(R^(m))C(O)O(R″), —(C₁-C₆         alkylenyl)-N(R^(m))C(O)N(R^(m))₂, or —(C₁-C₆         alkylenyl)-N(R^(m))S(O)₂N(R^(m))₂;     -   R^(h), at each occurrence, is independently hydrogen, C₁-C₆         alkyl, C₁-C₆ haloalkyl, or —(C₁-C₆ alkylenyl)-OR^(m);     -   R^(1a), R^(1b), R^(1c), R^(1d), and R^(2a), at each occurrence,         are each independently C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆         alkynyl, halogen, C₁-C₆ haloalkyl, oxo, —CN, NO₂, —OR^(m),         —OC(O)R^(n), —OC(O)N(R^(m))₂, —SR^(m), —S(O)₂R^(m),         —S(O)₂N(R^(m))₂, —C(O)R^(m), —C(O)OR^(m), —C(O)N(R^(m))₂,         —C(O)N(R^(m))S(O)₂R^(n), —N(R^(m))₂, —N(R^(m))(alkoxyalkyl),         —N(alkoxyalkyl)₂, —N(R^(m))C(O)R^(n), —N(R^(m))S(O)₂R^(n),         —N(R^(m))C(O)O(R^(n)), —N(R^(m))C(O)N(R^(m))₂,         —N(R^(m))S(O)₂N(R^(m))₂, —(C₁-C₆ alkylenyl)-CN, —(C₁-C₆         alkylenyl)-OR^(m), —(C₁-C₆ alkylenyl)-OC(O)R^(n), —(C₁-C₆         alkylenyl)-OC(O)N(R^(m))₂, —(C₁-C₆ alkylenyl)-SR^(m), —(C₁-C₆         alkylenyl)-S(O)₂R^(m), —(C₁-C₆ alkylenyl)-S(O)₂N(R^(m))₂,         —(C₁-C₆ alkylenyl)-C(O)R^(m), —(C₁-C₆ alkylenyl)-C(O)OR^(m),         —(C₁-C₆ alkylenyl)-C(O)N(R^(m))₂, —(C₁-C₆         alkylenyl)-C(O)N(R^(m))S(O)₂R^(n), —(C₁-C₆ alkylenyl)-N(R^(m))₂,         —(C₁-C₆ alkylenyl)-N(R^(m))C(O)R^(n), —(C₁-C₆         alkylenyl)-N(R^(m))S(O)₂R^(n), —(C₁-C₆         alkylenyl)-N(R^(m))C(O)O(R^(n)), —(C₁-C₆         alkylenyl)-N(R^(m))C(O)N(R^(n))₂, or —(C₁-C₆         alkylenyl)-N(R^(m))S(O)₂N(R^(n))₂;     -   R^(m), at each occurrence, is independently hydrogen, C₁-C₆         alkyl, or C₁-C₆ haloalkyl;     -   R^(n), at each occurrence, is independently C₁-C₆ alkyl or C₁-C₆         haloalkyl; and     -   R⁴ is hydrogen, C₁-C₃ alkyl, or C₁-C₃ haloalkyl;     -   with the proviso that when R¹ is C₁-C₆ alkyl or G^(1A), wherein         G^(1A) is optionally substituted phenyl, optionally substituted         5-6 membered monocyclic heteroaryl, or optionally substituted         4-7 membered monocyclic heterocycle, R² is C₁-C₆ alkyl, and R³         is G^(3A), then G^(3A) is not optionally substituted phenyl or         optionally substituted 5-6 membered monocyclic heteroaryl.

Exemplary compounds of formula (I) include, but are not limited to:

-   3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-(4-methoxyphenyl)-3-methyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclopentyl-4-(4-methoxyphenyl)-3-methyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(2-cyanoethyl)-4-(4-methoxyphenyl)-3-methyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(morpholin-4-yl)phenyl]-1-phenyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-[5-(trifluoromethyl)-1H-pyrazol-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-1-phenyl-4-[4-(piperidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[4-(4-methylpiperazin-1-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3,5-difluorophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-chlorophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-fluorophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-1-(3-methylphenyl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(1,1-dioxo-1λ⁶,4-thiazinan-4-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[2-(morpholin-4-yl)pyrimidin-5-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-(ethoxycarbonyl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-bromophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-(hydroxymethyl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-methylphenyl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-methoxyphenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-(oxan-4-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-phenyl-3-(propan-2-yl)-4-[4-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-1-phenyl-4-[4-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[2-chloro-4-(morpholin-4-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[4-(1-methyl-1,2,3,6-tetrahydropyridin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(3-fluoropyrrolidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-acetylpiperazin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3,5-dimethylphenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-[4-(trifluoromethoxy)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-1-[3-(morpholin-4-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[2-methoxy-4-(morpholin-4-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclopropyl-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-[3-(trifluoromethoxy)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(dimethylamino)phenyl]-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3,4-difluorophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(methanesulfonyl)phenyl]-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-1-(1-methylpiperidin-4-yl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-tert-butyl-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(2-chloropyridin-4-yl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3,     5-dimethyl-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1-[4-(trifluoromethoxy)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3,5-dichlorophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-(3-sulfamoylphenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-1-(1-methyl-1H-pyrazol-4-yl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-[1-(tert-butoxycarbonyl)azetidin-3-yl]-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(morpholin-4-yl)phenyl]-1-phenyl-3-(prop-1-en-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-cyanophenyl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(2-methoxypyridin-4-yl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-fluoro-5-methoxyphenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[4-(methanesulfonyl)piperazin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-(methylcarbamoyl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-(1-hydroxy-2-methylpropan-2-yl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(2-fluoropyridin-4-yl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-(2-oxo-1,2-dihydropyridin-4-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-carbamoylphenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-tert-butylpiperazin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(6-methoxypyridin-3-yl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[2-(dimethylamino)pyrimidin-5-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-(2-hydroxypropan-2-yl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-carbamoyl-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-3-methyl-4-[2-(morpholin-4-yl)pyrimidin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[3-bromo-4-(morpholin-4-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclopentyl-4-[2-(dimethylamino)pyrimidin-5-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(morpholin-4-yl)phenyl]-1-(oxan-3-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclopentyl-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[4-(methoxycarbonyl)piperazin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(1-acetylpiperidin-4-yl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[3-(dimethylamino)azetidin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(3,3-dimethylazetidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-3-methyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[2-(dimethylamino)pyrimidin-5-yl]-3-methyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-[1-(tert-butoxycarbonyl)pyrrolidin-2-yl]-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclopentyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-(1-acetylazetidin-3-yl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[2-(morpholin-4-yl)pyrimidin-5-yl]-1-phenyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[2-(morpholin-4-yl)pyrimidin-5-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-1-phenyl-4-{4-[4-(3,3,3-trifluoropropyl)piperazin-1-yl]phenyl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclopentyl-4-[6-(dimethylamino)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(dimethylamino)phenyl]-4-[2-(morpholin-4-yl)pyrimidin-5-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(dimethylamino)phenyl]-4-[6-(morpholin-4-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-[1-(methoxycarbonyl)azetidin-3-yl]-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-[(dimethylamino)methyl]-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[2-(dimethylamino)pyrimidin-5-yl]-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(dimethylamino)pyridin-3-yl]-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(dimethylamino)phenyl]-3-methyl-4-[2-(morpholin-4-yl)pyrimidin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-tert-butyl-1-cyclopentyl-4-[2-(dimethylamino)pyrimidin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-(1-hydroxy-2-methylpropan-2-yl)-4-[6-(morpholin-4-yl)pyridin-3-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[6-(dimethylamino)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-1-(1-methyl-2-oxo-1,2-dihydropyridin-4-yl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[1-(cyanomethyl)piperidin-4-yl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(cyclobutylamino)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(3,3-difluoroazetidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[4-(cyanomethyl)piperazin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[6-(dimethylamino)pyridin-3-yl]-3-methyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-tert-butyl-1-cyclopentyl-4-[2-(morpholin-4-yl)pyrimidin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-fluorophenyl)-3-methyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-[1-(tert-butoxycarbonyl)pyrrolidin-2-yl]-4-[6-(morpholin-4-yl)pyridin-3-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(2,4-difluorophenyl)-3-methyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(2,4-difluorophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclopentyl-3-methyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[4-(2-hydroxyethyl)piperazin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4,4-difluoropiperidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-cyanopiperidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-{4-[methyl(oxan-4-yl)amino]phenyl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(3,3-difluoropyrrolidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-{4-[(oxetan-3-yl)amino]phenyl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-(3-methyloxetan-3-yl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(2,6-dimethylmorpholin-4-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[cyclobutyl(methyl)amino]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[(3R,4R)-3,4-dihydroxypyrrolidin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1-[1-(2,2,2-trifluoroethyl)piperidin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-(morpholin-4-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid;     4-[4-(2,2-dimethylmorpholin-4-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(morpholin-4-yl)phenyl]-1-(oxolan-3-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(morpholin-4-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-(methoxymethyl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-1-phenyl-4-(piperidin-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(3-hydroxyazetidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(3-fluoroazetidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[4-(2-oxa-6-azaspiro[3.3]heptan-6-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-{4-[(1S,4S)-2-oxa-5-azabicyclo[2.2.1]heptan-5-yl]phenyl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(3,6-dihydro-2H-pyran-4-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-(1-methylcyclopropyl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-tert-butyl-1-cyclohexyl-4-[4-(dimethylamino)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-acetylpiperazin-1-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[2-(hydroxymethyl)morpholin-4-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[4-(8-oxa-3-azabicyclo[3.2.1]octan-3-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(azetidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(cyanomethyl)piperazin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-hydroxypiperidin-1-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(1-acetylpiperidin-4-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[1-(cyanomethyl)piperidin-4-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-{4-[methyl(oxetan-3-yl)amino]phenyl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[1-(cyanomethyl)pyrrolidin-3-yl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[1-(methoxycarbonyl)pyrrolidin-3-yl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-methoxypiperidin-1-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-hydroxypiperidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-{4-[(oxan-4-yl)amino]phenyl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(methanesulfonyl)piperazin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-tert-butyl-1-cyclohexyl-4-[2-(dimethylamino)pyrimidin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-[1-(cyanomethyl)azetidin-3-yl]-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-tert-butyl-1-cyclohexyl-4-[2-(morpholin-4-yl)pyrimidin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-(2-oxopiperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(azetidin-1-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(cyclohexylmethoxy)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(3-hydroxypyrrolidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[4-(2-oxa-7-azaspiro[3.5]nonan-7-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[(3S)-3-cyanopyrrolidin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(3-acetamidopyrrolidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-1-phenyl-4-(piperidine-1-carbonyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4,4-difluorocyclohexyl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(3,3-dimethylazetidin-1-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1-[1-(2,2,2-trifluoroethyl)piperidin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-methylphenyl)-4-(piperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[(1R,3R)-3-(benzyloxy)cyclohexyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(3-methoxyazetidin-1-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(3-fluoropyrrolidin-1-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[2-(dimethylamino)pyrimidin-5-yl]-3-[1-(methoxycarbonyl)azetidin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(3-fluoroazetidin-1-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-{6[(2-methoxyethyl)(methyl)amino]pyridin-3-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-acetamidophenyl)-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-{3-[(2-methoxyethyl)(methyl)amino]phenyl}-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-methylphenyl)-3-(propan-2-yl)-4-(pyrrolidin-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(3-fluoroazetidin-1-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-cyanopiperidin-1-yl)phenyl]-1-[3-(dimethylamino)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-[3-(dimethylamino)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{6-[(2-methoxyethyl)(methyl)amino]pyridin-3-yl}-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[6-(3,3-difluoropyrrolidin-1-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-{4-[(2-methoxyethyl)(methyl)amino]phenyl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-cyanopiperidin-1-yl)phenyl]-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(morpholin-4-yl)phenyl]-3-(oxolan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[(2-methoxyethyl)(methyl)amino]phenyl}-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(dimethylamino)phenyl]-4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(3-methoxypiperidin-1-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-cyanopiperidin-1-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-methoxypiperidin-1-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-3-cyclopropyl-4-[6-(dimethylamino)pyridin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   rac-1-[(1R,3R)-3-hydroxycyclohexyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   rac-1-[(1R,3S)-3-hydroxycyclohexyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[6-(2,6-dimethylmorpholin-4-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[6-(2,2-dimethylmorpholin-4-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(3-hydroxypiperidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[2-(4-cyanopiperidin-1-yl)pyrimidin-5-yl]-1-[3-(dimethylamino)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(dimethylamino)phenyl]-4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(morpholin-4-yl)phenyl]-1-[2-(morpholin-4-yl)pyridin-4-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-methylphenyl)-4-(2-oxa-7-azaspiro[3.5]nonan-7-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyano-4-methylpiperidin-1-yl)pyridin-3-yl]-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[2-(4-cyanopiperidin-1-yl)pyrimidin-5-yl]-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[(1R,3S)-3-methoxycyclohexyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-cyanopiperidin-1-yl)phenyl]-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(dimethylamino)phenyl]-4-{4-[methyl(oxan-4-yl)amino]phenyl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[methyl(oxan-4-yl)amino]phenyl}-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(2-methoxyethyl)(methyl)amino]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4,4-difluoropiperidin-1-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(morpholin-4-yl)phenyl]-1-[5-(morpholin-4-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(3-methoxyazetidin-1-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(hydroxymethyl)piperidin-1-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[(1R,3R)-3-methoxycyclohexyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-methylphenyl)-3-(propan-2-yl)-4-[3-(trifluoromethyl)pyrrolidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[5-(tert-butoxycarbonyl)hexahydropyrrolo[3,4-c]pyrrol-2(1H)-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[3-(dimethylamino)pyrrolidin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(3-cyanopyrrolidin-1-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-cyanopiperidin-1-yl)phenyl]-3-cyclobutyl-1-cyclohexyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-cyclobutyl-1-cyclohexyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-cyanopiperidin-1-yl)phenyl]-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[6-(3-fluoropiperidin-1-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[6-(3-methoxypyrrolidin-1-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(3-hydroxyazetidin-1-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[5-(cyanomethyl)hexahydropyrrolo[3,4-c]pyrrol-2(1H)-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(methoxymethyl)piperidin-1-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(2-methoxyethyl)piperidin-1-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-chloropyridin-2-yl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{2-[(2-methoxyethyl)(methyl)amino]pyrimidin-5-yl}-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[4-(cyanomethyl)piperazin-1-yl]phenyl}-1-(3-methoxyphenyl)-3-methyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(5-acetylhexahydropyrrolo[3,4-c]pyrrol-2(1H)-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[1-(tert-butoxycarbonyl)octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[2-(4-cyanopiperidin-1-yl)pyrimidin-5-yl]-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-{2-[(2-methoxyethyl)(methyl)amino]pyrimidin-5-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[(2-methoxyethyl)(methyl)amino]phenyl}-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(azetidin-1-yl)phenyl]-4-{6-[(2-methoxyethyl)(methyl)amino]pyridin-3-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(azetidin-1-yl)phenyl]-4-{4-[methyl(oxan-4-yl)amino]phenyl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(morpholin-4-yl)phenyl]-1-[4-(morpholin-4-yl)pyridin-2-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-fluorophenyl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3,4-difluorophenyl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(morpholin-4-yl)phenyl]-1-[6-(morpholin-4-yl)pyridin-2-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3,5-difluorophenyl)-4-{4-[methyl(oxan-4-yl)amino]phenyl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3,5-difluorophenyl)-4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-cyanopiperidin-1-yl)phenyl]-3-cyclobutyl-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-cyclobutyl-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[methyl(oxan-4-yl)amino]phenyl}-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[methyl(oxan-4-yl)amino]phenyl}-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{6-[(2-methoxyethyl)(methyl)amino]pyridin-3-yl}-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-{4-[methyl(oxan-4-yl)amino]phenyl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(1-acetyloctahydro-5H-pyrrolo[3,2-c]pyridin-5-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[1-(cyanomethyl)octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(methanesulfonyl)piperidin-1-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-methylphenyl)-4-(7-oxa-2-azaspiro[3.5]nonan-2-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[2-(4-cyanopiperidin-1-yl)pyrimidin-5-yl]-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(propan-2-yl)-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-cyanopiperidin-1-yl)phenyl]-3-(propan-2-yl)-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-methylphenyl)-4-(8-oxa-2-azaspiro[4.5]decan-2-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-cyanopiperidin-1-yl)-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-(4-methoxypiperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-(piperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[4-(hydroxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[6-(dimethylamino)pyridin-2-yl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3,5-difluorophenyl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1-[3-(trifluoromethoxy)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(dimethylamino)phenyl]-3-(propan-2-yl)-4-[3-(trifluoromethyl)pyrrolidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(1,1-difluoro-5-azaspiro[2.4]heptan-5-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[3-(methanesulfonyl)pyrrolidin-1-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(2-azaspiro[3.3]heptan-2-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-methylphenyl)-4-(5-oxa-2-azaspiro[3.5]nonan-2-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{6-[bis(2-methoxyethyl)amino]pyridin-3-yl}-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-{6-[methyl(oxolan-3-yl)amino]pyridin-3-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3,4-difluorophenyl)-4-{4-[methyl(oxan-4-yl)amino]phenyl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-(3,4-difluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-3-(propan-2-yl)-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-cyanopiperidin-1-yl)phenyl]-1-(3,5-difluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-fluorophenyl)-4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-fluorophenyl)-4-{4-[methyl(oxan-4-yl)amino]phenyl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-(3-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-cyanopiperidin-1-yl)phenyl]-1-(3-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-3-(propan-2-yl)-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-(4-methyl-3-oxo-1-oxa-4,9-diazaspiro[5.5]undecan-9-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[3-(methoxymethyl)-3-methylazetidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-(3-oxohexahydroimidazo[1,5-a]pyrazin-2(3H)-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(methoxymethyl)piperidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-acetamidopiperidin-1-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-(7-oxa-2-azaspiro[3.5]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[3-(methoxymethyl)azetidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3R)-3-methoxypyrrolidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3S)-3-methoxypyrrolidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-fluoropiperidin-1-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3R)-3-fluoropyrrolidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(3,3-difluoropyrrolidin-1-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3S)-3-fluoropyrrolidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-(3-oxotetrahydro-3H-[1,3]oxazolo[3,4-a]pyrazin-7(1H)-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[3-(morpholin-4-yl)azetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[(methanesulfonyl)amino]piperidin-1-yl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(3-azabicyclo[3.1.     O]hexan-3-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-1-phenyl-4-[4-(pyrrolidine-1-carbonyl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-(6-oxa-2-azaspiro[3.4]octan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(2-azaspiro[3.4]octan-2-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-(6-oxa-2-azaspiro[3.5]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(2-azaspiro[3.5]nonan-2-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(5-azaspiro[2.5]octan-5-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-(1-oxa-7-azaspiro[4.4]nonan-7-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-(5-oxa-2-azaspiro[3.5]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-(6-oxo-2,     7-diazaspiro[4.4]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[(1S)-2-(dimethylamino)-1-fluoroethyl]piperidin-1-yl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-(1,4-oxazepan-4-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3-fluorophenyl)-4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(3,5-difluorophenyl)-4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(2-methoxyethoxy)piperidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(dimethylcarbamoyl)piperidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(methanesulfonyl)-1,4-diazepan-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(3-methoxypropyl)piperazin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[4-(morpholine-4-carbonyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[2-(dimethylamino)-2-oxoethyl]piperazin-1-yl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[2-(4-cyanopiperidin-1-yl)pyrimidin-5-yl]-1-(2,4-difluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-(2,4-difluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-cyanopiperidin-1-yl)phenyl]-1-(2,4-difluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(dimethylamino)phenyl]-4-(piperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-cyanopiperidin-1-yl)-1-[3-(dimethylamino)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(dimethylamino)phenyl]-4-(4-methoxypiperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(dimethylamino)phenyl]-4-[4-(hydroxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-(1-methylcyclobutyl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{[cis-3-(1,1-dioxo-1λ⁶,4-thiazinan-4-yl)cyclobutyl]oxy}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[2-(1,1-dioxo-1λ⁶,4-thiazinan-4-yl)ethoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(2S)-2-fluoro-2-(oxan-4-yl)ethoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(2R)-2-fluoro-2-(oxan-4-yl)ethoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-{[(3S)-1-methylpyrrolidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-{[(3R)-1-methylpyrrolidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[(1-methylpiperidin-4-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{[cis-3-(dimethylamino)cyclobutyl]oxy}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[(oxetan-3-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid;     3-methyl-1-phenyl-4-[2-(pyrrolidin-1-yl)ethoxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-{[(3R)-1-methylpiperidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[(2-oxaspiro[3.3]heptan-6-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-1-phenyl-4-{[trans-3-(piperidin-1-yl)cyclobutyl]oxy}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-1-phenyl-4-{[cis-3-(piperidin-1-yl)cyclobutyl]oxy}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[2-(3,3-difluorocyclobutyl)ethoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(fluoromethyl)piperidin-1-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(3-fluorophenyl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(3,4-difluorophenyl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-(1-methyl-1H-pyrrol-3-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-(1,3-dimethyl-1H-pyrazol-4-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(3,5-difluorophenyl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(morpholin-4-yl)phenyl]-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(3-fluoro-4-methylphenyl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(morpholin-4-yl)phenyl]-1-[4-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-[4-(dimethylamino)phenyl]-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-methoxypiperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(3-methyl-2-oxo-1-oxa-3,8-diazaspiro[4.5]decan-8-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(3-azaspiro[5.5]undecan-3-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-3-(propan-2-yl)-4-[1-(propan-2-yl)-1H-pyrazol-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-(1-methyl-1H-pyrrol-2-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-3-(propan-2-yl)-4-(1H-pyrazol-4-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-(1-oxo-2,3-dihydro-1H-isoindol-5-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-(oxan-3-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[2-(3-cyanopiperidin-1-yl)pyrimidin-5-yl]-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[2-oxo-2-(pyrrolidin-1-yl)ethoxy]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(dimethylamino)phenyl]-4-[4-(methoxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(propan-2-yl)-1-[2-(pyrrolidin-1-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-(1-methyl-1H-pyrazol-5-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[1-(tert-butoxycarbonyl)-1,2,3,6-tetrahydropyridin-4-yl]-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-{4-[(propan-2-yl)oxy]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(methoxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(2-{[1-(tert-butoxycarbonyl)piperidin-4-yl](methyl)amino}pyrimidin-5-yl)-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[(3-methyloxetan-3-yl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(4-methoxycyclohexyl)oxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[2-fluoro-2-(oxan-4-yl)ethoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3-fluoro-1-methylpyrrolidin-3-yl)methoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(2S)-2-fluoro-2-(1-methylpiperidin-4-yl)ethoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(2R)-2-fluoro-2-(1-methylpiperidin-4-yl)ethoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{[3-fluoro-1-(oxetan-3-yl)piperidin-3-yl]methoxy}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3,3-difluorocyclopentyl)methoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-methyl-4-[2-oxo-2-(piperidin-1-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{[1-(methanesulfonyl)cyclobutyl]methoxy}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{2-[cyclopropyl(2-methylpropyl)amino]ethoxy}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3,3-difluoro-1-methylcyclobutyl)methoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{[1-(fluoromethyl)cyclopropyl]methoxy}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{[1-(2-methoxyethyl)cyclopropyl]methoxy}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(2,2-difluorocyclopentyl)methoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(morpholin-4-yl)phenyl]-1-phenyl-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[4-(methoxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-cyanopiperidin-1-yl)phenyl]-3-(propan-2-yl)-1-[2-(pyrrolidin-1-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-(4-methoxypiperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[4-(hydroxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-butoxypiperidin-1-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[4-(2-methylpropoxy)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-(4-methoxy-4-methylpiperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-(1-oxa-7-azaspiro[3.5]nonan-7-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[3-(difluoromethyl)piperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-(6-oxa-2-azaspiro[3.5]nonan-2-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-(1-oxa-8-azaspiro[4.5]decan-8-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-3-(propan-2-yl)-4-(2,2,6,6-tetramethyl-3,6-dihydro-2H-pyran-4-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(2-methoxyethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(2-azaspiro[3.4]octan-2-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(methoxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(3-azabicyclo[3.1.0]hexan-3-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(cyclohexylmethoxy)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-(piperidin-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid;     4-(2-azaspiro[3.5]nonan-2-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-cyanopiperidin-1-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(methanesulfonyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-methoxypiperidin-1-yl)-3-(propan-2-yl)-1-[2-(pyrrolidin-1-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-cyclobutyl-1-[2-(pyrrolidin-1-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[2-(oxan-4-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(2S)-2-fluoro-2-(oxan-4-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-cyclobutyl-1-[2-(morpholin-4-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(oxan-4-yl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(methoxymethyl)azetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(5-azaspiro[2.5]octan-5-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(3,3-difluorocyclobutyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(cis-3-methoxycyclobutyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(2-methoxyethyl)(methyl)amino]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(1,1-difluoro-5-azaspiro[2.4]heptan-5-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(5-oxa-2-azaspiro[3.5]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(7-oxa-2-azaspiro[3.5]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(2-azaspiro[3.3]heptan-2-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[(benzyloxy)methyl]piperidin-1-yl}-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(cis-4-methoxycyclohexyl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(trans-4-methoxycyclohexyl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(3,3-dimethylcyclobutyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[4-(methoxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(cis-3-fluorocyclobutyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(trans-3-fluorocyclobutyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(2R)-2-fluoro-2-(oxan-4-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3,3-difluorocyclopentyl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[2-(1,1-dioxo-1λ⁶,4-thiazinan-4-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-[2-(morpholin-4-yl)pyridin-4-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[4-(2-methoxypropan-2-yl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(cis-3-tert-butoxycyclobutyl)(methyl)amino]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(3-methylazetidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(3,3-difluoropyrrolidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-[3-(trifluoromethyl)pyrrolidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-[4-(pyrrolidin-1-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-fluoropiperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3R,4R)-3,4-dihydroxypyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3     S,4S)-3,4-dihydroxypyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[2-(dimethylamino)ethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[2-(diethylamino)ethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(cyclopropylmethyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-cyclobutylpiperazin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(3-fluoro-3-methylazetidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(8-azaspiro[4.5]decan-8-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(3,3-difluoro-1-oxa-8-azaspiro[4.5]decan-8-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(1′-methyl[4,4′-bipiperidin]-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(1R)-2-(dimethylamino)-1-fluoroethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(1S)-2-(dimethylamino)-1-fluoroethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(1S)-1-fluoro-2-hydroxyethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(1R)-1-fluoro-2-hydroxyethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-fluoro-4-[(2-methoxyethoxy)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(ethoxymethyl)-3-fluoropiperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(ethoxymethyl)-4-fluoropiperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{3-fluoro-3-[(2-methoxyethoxy)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-fluoro-4-(methoxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3R,4R)-3-fluoro-4-hydroxypiperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3R,4R)-4-fluoro-3-hydroxypiperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-[3-(piperidin-1-yl)azetidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3R)-3-(methanesulfonyl)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(3-methoxypiperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-oxo-1-(propan-2-yl)-1,3,8-triazaspiro[4.5]decan-8-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-[4-(2,2,2-trifluoroethyl)piperazin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(3-hydroxypropyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[2-oxo-2-(pyrrolidin-1-yl)ethyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(azepan-1-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[2-(morpholin-4-yl)-2-oxoethyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(7R,8aS)-7-hydroxyhexahydropyrrolo[1,2-a]pyrazin-2(1H)-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3,3-difluoro-1-methylcyclobutyl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[2-(3,3-difluorocyclobutyl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{2-[(oxetan-3-yl)(propan-2-yl)amino]ethoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(1-acetyl-4-fluoropiperidin-4-yl)methoxy]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[(2S)-oxolan-2-yl]methoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[2-(3-methoxyazetidin-1-yl)-2-oxoethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(2R)-2-fluoro-2-(1-methylpiperidin-4-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{2-[(oxetan-3-yl)oxy]ethoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{2-[1-(2-methoxyethyl)cyclopropyl]ethoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[1-(2-methoxyethyl)cyclopropyl]methoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(2,2-difluorocyclopentyl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(morpholin-4-yl)propoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[2-(1,3-dioxan-2-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(3-fluoropropoxy)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3-methyloxetan-3-yl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(1,3-dimethoxypropan-2-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[cis-3-(dimethylamino)cyclobutyl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(2-methyl-1,3-dioxan-5-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[(3S)-1-methylpiperidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(2-oxaspiro[3.3]heptan-6-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[(3R)-1-methylpiperidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-[(1-acetylazetidin-3-yl)oxy]-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(1-methoxyethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-[4-(1,1,1-trifluoro-2-methoxypropan-2-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(diethylcarbamoyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-hydroxypiperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[2-(1,4-dimethyl-6-oxo-1,6-dihydropyrimidin-5-yl)ethyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(4aS,7aR)-4-methyl-3-oxohexahydropyrrolo[3,4-b][1,4]oxazin-6(2H)-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(3-oxopiperazin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(5aS,8aS)-2-oxooctahydropyrrolo[3,4-b]azepin-7(1H)-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(2R)-4,4-difluoro-2-(hydroxymethyl)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(2S,4S)-4-fluoro-2-(hydroxymethyl)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-fluoro-3-(methoxymethyl)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3R,4S)-3-fluoro-4-hydroxypiperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(ethoxymethyl)-3-fluoropyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(hydroxymethyl)-3-methylazetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3S)-3-methoxypyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(2,2-difluoroethoxy)azetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(2R,4S)-4-fluoro-2-(hydroxymethyl)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(7S,8aS)-7-fluorohexahydropyrrolo[1,2-a]pyrazin-2(1H)-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(4aS,7aS)-4-methyl-3-oxohexahydropyrrolo[3,4-b][1,4]oxazin-6(2H)-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-fluoro-4-(hydroxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(1-oxa-7-azaspiro[4.4]nonan-7-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(methanesulfonyl)amino]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(1-fluoro-2-hydroxyethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(methoxymethyl)-3-methylazetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3R)-3-methoxypyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(methanesulfonyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{6-[bis(2-methoxyethyl)amino]pyridin-3-yl}-1-[2-(morpholin-4-yl)pyridin-4-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(methoxymethyl)piperidin-1-yl]-1-[2-(morpholin-4-yl)pyridin-4-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-methoxy-4-(methoxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3S)-3-fluoropyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(3,3-difluoroazetidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(2-oxo-1,3-oxazolidin-3-yl)azetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(3-ethyl-3-fluoroazetidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[2-(hydroxymethyl)morpholin-4-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{3-fluoro-3-[(2-methoxyethoxy)methyl]pyrrolidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(cis-3-hydroxycyclobutyl)(methyl)amino]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(6-oxa-2-azaspiro[3.4]octan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3R,4S)-4-fluoro-3-hydroxypiperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(3-hydroxy-3-methylazetidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(6-oxo-2,     7-diazaspiro[4.4]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(2S)-4,4-difluoro-2-(hydroxymethyl)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(ethoxycarbonyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[2-(cyclohexylamino)-2-oxoethyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3R)-3-fluoropyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(3-methoxyazetidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(2-hydroxy-7-azaspiro[3.5]nonan-7-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3R)-3-(hydroxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(1,4-oxazepan-4-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-hydroxy-4-(2-hydroxyethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(cyclobutylmethyl)-4-[4-(methoxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(methoxymethyl)piperidin-1-yl]-1-(2-methylpropyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   rac-4-[(3aR,7aS)-1-(tert-butoxycarbonyl)octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-phenyl-3-[(pyrrolidin-3-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(trans-3-methylcyclobutyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-{[1-(tert-butoxycarbonyl)pyrrolidin-3-yl]oxy}-4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-{[1-(tert-butoxycarbonyl)piperidin-4-yl]oxy}-4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{methyl[(oxan-4-yl)methyl]amino}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-[4-(2-propoxyethyl)piperazin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-{2-[(piperidin-1-yl)methyl]morpholin-4-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-{4-[(pyrrolidin-1-yl)methyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[3-(morpholin-4-yl)propyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[2-(dimethylamino)-2-oxoethyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(2-cyanoethyl)piperazin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{2-[(dimethylamino)methyl]morpholin-4-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-methylpiperazin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(methyl     {[1-(2-methylpropyl)piperidin-4-yl]methyl}amino)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{methyl[2-(morpholin-4-yl)ethyl]amino}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(2-ethoxyethyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3R)-3-(dimethylamino)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3S)-3-(dimethylamino)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[2-(methylamino)-2-oxoethyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(morpholin-4-yl)acetyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(2-methoxyethyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(oxolan-2-yl)methyl]-1,4-diazepan-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-{3-[(propan-2-yl)oxy]azetidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[2-(morpholin-4-yl)ethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-([1,4′-bipiperidin]-1′-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3R)-3-(morpholin-4-yl)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(4,4-difluorocyclohexyl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(oxan-4-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[(1S,2S)-2-methoxycyclohexyl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3-ethyloxetan-3-yl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[(3R)-oxolan-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[(3S)-oxolan-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-methoxy-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(cyclobutyloxy)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[2-(2-methoxyethoxy)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3aR,7aS)-1-acetyloctahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3aS,7aR)-1-acetyloctahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(methoxymethyl)piperidin-1-yl]-1-[2-(morpholin-4-yl)pyrimidin-4-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[(oxan-4-yl)methyl]amino}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-[(oxolan-3-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-[(oxetan-3-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{methyl[(1-methylpiperidin-3-yl)methyl]amino}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4,4-difluoropiperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-fluoro-3-(methoxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-[2-(trifluoromethyl)morpholin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(cyclopentyloxy)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{[cis-3-(azetidin-1-yl)cyclobutyl]oxy}-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(1-cyclohexylazetidin-3-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3,3-difluorocyclobutyl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(1-methylazetidin-3-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[3-(dimethylamino)phenyl]-4-[(oxan-4-yl)methoxy]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[(oxan-4-yl)methoxy]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[2-(oxan-4-yl)ethoxy]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(2-methoxypropan-2-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[3-(dimethylamino)propoxy]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[3-(morpholin-4-yl)propoxy]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[(3-methyloxetan-3-yl)methoxy]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[(oxolan-2-yl)methoxy]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   rac-3-cyclobutyl-1-phenyl-4-[(3aR,7aS)-1-{[(propan-2-yl)oxy]carbonyl}octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(dimethylamino)butoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(1-acetylpiperidin-4-yl)oxy]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-(2,2,2-trifluoroethoxy)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{2-[2-(dimethylamino)ethoxy]ethoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[(2S)-1-(dimethylamino)propan-2-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(4,4-difluorocyclohexyl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[(2R)-5-oxopyrrolidin-2-yl]methoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[(4R)-2,2-dimethyl-1,3-dioxolan-4-yl]methoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[(3S)-6-oxopiperidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(5-ethyl-1,3-dioxan-5-yl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[(3-endo)-8-methyl-8-azabicyclo[3.2.1]octan-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(5-methyl-1,3-dioxan-5-yl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[2-(1,4-dioxa-8-azaspiro[4.5]decan-8-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(diethylamino)propoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{2-[cyclohexyl(oxetan-3-yl)amino]ethoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[4-fluoro-1-(methanesulfonyl)piperidin-4-yl]methoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[4-(methanesulfonyl)oxan-4-yl]methoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-[2-(pyrrolidin-1-yl)ethoxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[2-(methanesulfonyl)-2-methylpropoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(1-methylcyclopropyl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[2-(1-methylcyclopropyl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[1-(methanesulfonyl)cyclobutyl]methoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(2-cyclohexylethoxy)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(4-methylpiperazin-1-yl)propoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(dimethylamino)propoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(dimethylamino)-2,2-dimethylpropoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[2-(dimethylamino)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{[1,3-bis(dimethylamino)propan-2-yl]oxy}-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-[2-(piperidin-1-yl)ethoxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[2-(2-oxoimidazolidin-1-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{[1,3-bis(morpholin-4-yl)propan-2-yl]oxy}-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-[3-(piperidin-1-yl)propoxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[2-(azepan-1-yl)ethoxy]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[2-(4-methyl-1,4-diazepan-1-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[(2s,4r)-5-methyl-5-azaspiro[3.4]octan-2-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(1-{3-[(diethylamino)methyl]oxetan-3-yl}azetidin-3-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-{[1-(propan-2-yl)piperidin-4-yl]oxy}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(cycloheptyloxy)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid;     3-cyclobutyl-4-(cyclooctyloxy)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid;     3-cyclobutyl-4-{[(3R)-1-methylpyrrolidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{[(3S)-1-methylpyrrolidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3,3-difluoro-1-methylcyclobutyl)methoxy]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[3-(piperidin-1-yl)propoxy]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(1,3-dimethoxypropan-2-yl)oxy]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-({[(2S)-oxolan-2-yl]methyl}amino)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[4-(2-hydroxypropan-2-yl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[4-(methoxymethyl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[(oxan-4-yl)methoxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(2-hydroxypropan-2-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(dimethylamino)piperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-(1′-methyl[4,4′-bipiperidin]-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(1-acetylpiperidin-4-yl)methoxy]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{[1-(methoxycarbonyl)piperidin-4-yl]methoxy}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[(oxane-4-carbonyl)amino]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(cyanomethyl)-4-hydroxypiperidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(ethoxymethyl)-4-fluoropiperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-fluoro-4-[(2-methoxyethoxy)methyl]piperidin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3R,4R)-3-fluoro-4-hydroxypiperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-fluoro-4-(methoxymethyl)piperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{3-fluoro-3-[(2-methoxyethoxy)methyl]piperidin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3S)-3-{[(tert-butoxycarbonyl)amino]methyl}pyrrolidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3R)-3-{[(tert-butoxycarbonyl)amino]methyl}pyrrolidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(1,1-dioxo-1λ⁶,4-thiazinan-4-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3R)-3-{[(tert-butoxycarbonyl)(methyl)amino]methyl}pyrrolidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3S)-3-{[(tert-butoxycarbonyl)(methyl)amino]methyl}pyrrolidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{(3S)-3-[(methylamino)methyl]pyrrolidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(2,6-dimethylpyridin-4-yl)-4-[4-(methoxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(methoxymethyl)piperidin-1-yl]-1-(2-methoxypyridin-4-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-[3-(pyrrolidin-1-yl)azetidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(oxolan-2-yl)methyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(1-methoxypropan-2-yl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[1-(morpholin-4-yl)ethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(1,3-dioxolan-2-yl)methyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(2-methoxyethoxy)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-{4-[(piperidin-1-yl)methyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[2-(4-methylpiperidin-1-yl)ethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(2,6-dimethylmorpholin-4-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(diethylamino)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[{3-[cyclohexyl(methyl)amino]propyl}(methyl)amino]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-[4-(propan-2-yl)-1,4-diazepan-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3aR,6aS)-5-(2-methylpropyl)hexahydropyrrolo[3,4-c]pyrrol-2(1H)-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-([1,4′-bipiperidin]-1′-yl)-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[4-(2-methoxyethyl)piperazin-1-yl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[2-(4-methylpiperazin-1-yl)ethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(ethoxyacetyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3R)-3-(2-oxopyrrolidin-1-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4′-methyl[1,4′-bipiperidin]-1′-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(9-methyl-3,9-diazaspiro[5.5]undecan-3-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(1,4-dioxa-8-azaspiro[4.5]decan-8-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(2-methylpropoxy)carbonyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-methyl-1,4-diazepan-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-acetylpiperazin-1-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(3-methoxypropyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-cyclopentyl-1,4-diazepan-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(3R)-3-hydroxypiperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-(4-propylpiperazin-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(dimethylcarbamoyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(morpholin-4-yl)azetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-butyl-1,4-diazepan-1-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(morpholine-4-carbonyl)[1,4′-bipiperidin]-1′-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-(4-propyl-1,4-diazepan-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(1,4-dioxa-7-azaspiro[4.4]nonan-7-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[2-(2-hydroxyethoxy)ethyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-[(3R)-3-(piperidin-1-yl)pyrrolidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(7-cyano-5-oxa-2-azaspiro[3.4]octan-2-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[3-(4-methyl-1,4-diazepan-1-yl)-3-oxopropyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(dimethylcarbamoyl)-4-(2-oxopyrrolidin-1-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(cyclohexylmethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(6-oxa-2-azaspiro[3.5]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[(8aR)-hexahydropyrrolo[1,2-a]pyrazin-2(1H)-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(2-hydroxyethyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[3-(4-methylmorpholin-2-yl)azetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(3-{4-[methyl(oxetan-3-yl)amino]piperidin-1-yl}azetidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{3-[4-(morpholin-4-yl)piperidin-1-yl]azetidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[1-(2-ethoxyethyl)piperidin-4-yl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[1-(2-hydroxypropyl)piperidin-4-yl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[3-(dimethylamino)propyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[4-(2-ethoxyethyl)piperazin-1-yl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-{4-[2-(piperidin-1-yl)ethoxy]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[3-(diethylamino)propyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-{4-[3-(piperidin-1-yl)propyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-{4-[3-(pyrrolidin-1-yl)propyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[ethyl(oxetan-3-yl)amino]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[methyl(oxetan-3-yl)amino]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[1′-(oxetan-3-yl)[4,4′-bipiperidin]-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(dimethylamino)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(4-cyclopropylpiperazin-1-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(4-methylpiperazine-1-carbonyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[3-(4-methylmorpholin-2-yl)azetidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[1-(2-ethoxyethyl)piperidin-4-yl]piperazin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{4-[1-(2-hydroxypropyl)piperidin-4-yl]piperazin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(1-cyclopropylpiperidin-4-yl)piperazin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{4-[4-(oxetan-3-yl)piperazin-1-yl]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[4-(2-ethoxyethyl)piperazin-1-yl]piperidin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{4-[4-(2-methoxyethyl)piperazin-1-yl]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[3-(diethylamino)propyl]piperidin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{4-[3-(piperidin-1-yl)propyl]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-3-(propan-2-yl)-4-{4-[3-(pyrrolidin-1-yl)propyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[ethyl(oxetan-3-yl)amino]piperidin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{4-[methyl(oxetan-3-yl)amino]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[1′-(oxetan-3-yl)[4,4′-bipiperidin]-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[4-(4-methylpiperazin-1-yl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(4-cyclopropylpiperazin-1-yl)piperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[4-(4-methylpiperazine-1-carbonyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(4-methylpiperazin-1-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-(3-{4-[methyl(oxetan-3-yl)amino]piperidin-1-yl}azetidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{3     [4-(morpholin-4-yl)piperidin-1-yl]azetidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[3-(dimethylamino)propyl]piperazin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[4-methyl-4-(4-methylpiperazin-1-yl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{4-[2-(piperidin-1-yl)ethoxy]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-5-methyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[4-(4-methylpiperazine-1-carbonyl)phenyl]-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[3-(morpholin-4-yl)azetidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-3-(propan-2-yl)-4-(4-propyl-1,4-diazepan-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-cyclobutyl-1,4-diazepan-1-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-butyl-1,4-diazepan-1-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-(4-methyl-1,4-diazepan-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[(8aR)-hexahydropyrrolo[1,2-a]pyrazin-2(1H)-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-acetylpiperazin-1-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-ethylpiperazin-1-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[4-(2-hydroxyethyl)piperazin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(dimethylcarbamoyl)piperazin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(ethoxyacetyl)piperazin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[4-(3-methoxypropyl)piperazin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-3-(propan-2-yl)-4-(4-propylpiperazin-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{4-[2-(2-hydroxyethoxy)ethyl]piperazin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{4-[3-(4-methyl-1,4-diazepan-1-yl)-3-oxopropyl]piperazin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(cyclohexylmethyl)piperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-(9-methyl-3,9-diazaspiro[5.5]undecan-3-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(1,4-dioxa-8-azaspiro[4.5]decan-8-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[(3R)-3-hydroxypiperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-(4′-methyl[1,4′-bipiperidin]-1′-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{4-[2-(4-methylpiperazin-1-yl)ethyl]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[(3R)-3-(piperidin-1-yl)pyrrolidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(diethylamino)piperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-tert-butylpiperazin-1-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-3-(propan-2-yl)-4-{4-[1-(pyrrolidin-1-yl)ethyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{4-[(piperidin-1-yl)methyl]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{4-[(1-methylpiperidin-3-yl)methyl]piperazin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{4-[(oxolan-2-yl)methyl]piperazin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[4-(1-methoxypropan-2-yl)piperazin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-3-(propan-2-yl)-4-[3-(pyrrolidin-1-yl)azetidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-3-(propan-2-yl)-4-[4-(propan-2-yl)-1,4-diazepan-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[(3aR,6aS)-5-(2-methylpropyl)hexahydropyrrolo[3,4-c]pyrrol-2(1H)-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-ethyl-1,4-diazepan-1-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-(4-hydroxy-4-{[methyl(propan-2-yl)amino]methyl}piperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{4-[methyl(propan-2-yl)amino]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[2-(diethylamino)ethyl]piperazin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-[4-(1-methylpiperidin-4-yl)piperazin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-{[(3R)-3-(methoxymethyl)pyrrolidin-1-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-{[(3R)-3-methoxypyrrolidin-1-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-{[(3S)-3-(methoxymethyl)pyrrolidin-1-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[1-(morpholin-4-yl)ethyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-cyclohexyl-4-{4-[(morpholin-4-yl)methyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-cyclohexyl-4-{4-[2-(morpholin-4-yl)ethyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-(cyclobutyloxy)-1-cyclohexyl-4-{4-[(morpholin-4-yl)methyl]phenyl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-cyclohexyl-4-[4-(pyridin-4-yl)piperazin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[2-(morpholin-4-yl)ethyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-3-(propan-2-yl)-4-{4-[(pyrrolidin-1-yl)methyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-{4-[1-(pyrrolidin-1-yl)ethyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(3-oxo-2,8-diazaspiro[4.5]decan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-{4-[(2-methylpropoxy)carbonyl]piperazin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(2-methoxypyridin-4-yl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(methoxymethyl)piperidin-1-yl]-1-[2-(oxan-4-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-phenyl-4-[4-(propan-2-yl)piperazin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-[2-(oxan-4-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(3-methylphenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[(morpholin-4-yl)methyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(3-methoxyphenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-[4-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluoro-3-methylphenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(3-fluorophenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(3-fluoroazetidin-1-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(3,3-difluoropyrrolidin-1-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(3-methoxyazetidin-1-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(3,3-difluoropiperidin-1-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-{[3-(methoxymethyl)azetidin-1-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-{[(3R)-3-fluoropyrrolidin-1-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-{[(3S)-3-fluoropyrrolidin-1-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(1,4-oxazepan-4-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-{[3-(2,2-difluoroethoxy)azetidin-1-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(6-oxa-2-azaspiro[3.5]nonan-2-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(6-oxa-2-azaspiro[3.4]octan-2-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-{[(7S,8aS)-7-fluorohexahydropyrrolo[1,2-a]pyrazin-2(1H)-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(4-formyl-1,4-diazepan-1-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(2-oxa-7-azaspiro[3.5]nonan-7-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(4-methoxypiperidin-1-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(2-oxa-6-azaspiro[3.4]octan-6-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(4-formylpiperazin-1-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-{4-[(3-azabicyclo[3.1.0]hexan-3-yl)methyl]piperidin-1-yl}-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-{4-[(5-methyl-6-oxo-2-oxa-5,8-diazaspiro[3.5]nonan-8-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[4-(3-fluoropyrrolidin-1-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(3-cyanoazetidin-1-yl)piperidin-1-yl]-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[4-(3-methoxypyrrolidin-1-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4-fluoro[1,4′-bipiperidin]-1′-yl)-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(4,4-difluoro[1,4′-bipiperidin]-1′-yl)-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(2-cyanomorpholin-4-yl)piperidin-1-yl]-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[4-(2-oxa-5-azabicyclo[2.2.1]heptan-5-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[2-(methoxymethyl)morpholin-4-yl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[methyl(oxan-4-yl)amino]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-{2-[(propan-2-yl)oxy]pyridin-4-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-[2-(benzyloxy)pyridin-4-yl]-3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[(morpholin-4-yl)methyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[(4-methylpiperazin-1-yl)methyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-{[4-(methoxymethyl)piperidin-1-yl]methyl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-cyano[1,4′-bipiperidin]-1′-yl)-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-{4-[4-(dimethylamino)piperidine-1-carbonyl]phenyl}-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[3-(pyrrolidin-1-yl)-1-oxa-8-azaspiro[4.5]decan-8-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-3-[(propan-2-yl)oxy]-4-{4-[4-(propan-2-yl)piperazin-1-yl]phenyl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-cyclohexyl-4-[4-(2-methylpyridin-4-yl)piperazin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-cyclohexyl-4-{6-[4-(propan-2-yl)piperazin-1-yl]pyridin-3-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-cyclohexyl-4-{4-[1-(morpholin-4-yl)ethyl]phenyl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-cyclohexyl-4-{4-[4-(propan-2-yl)piperazin-1-yl]phenyl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-cyclohexyl-4-[6-(4-cyclopropylpiperazin-1-yl)pyridin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[3-(trifluoromethyl)pyrrolidin-1-yl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[4-(3-cyanopyrrolidin-1-yl)piperidin-1-yl]-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(3-cyano[1,4′-bipiperidin]-1′-yl)-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(3-fluoro[1,4′-bipiperidin]-1′-yl)-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[4-(3-methoxyazetidin-1-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[3-(trifluoromethyl)[1,4′-bipiperidin]-1′-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-(3-methoxy[1,4′-bipiperidin]-1′-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(2,2-dimethylmorpholin-4-yl)piperidin-1-yl]-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-cyclohexyl-4-[6-(4-methylpiperazin-1-yl)pyridin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-cyclohexyl-4-{6-[4-(2-methoxyethyl)piperazin-1-yl]pyridin-3-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[4-(propan-2-yl)piperazin-1-yl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-cyclohexyl-4-{4-[4-(propan-2-yl)piperazin-1-yl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3S)-4-benzyl-3-methylpiperazin-1-yl]-3-cyclobutyl-1-cyclohexyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-[(3R)-4-benzyl-3-methylpiperazin-1-yl]-3-cyclobutyl-1-cyclohexyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-[4-(4-methylpiperazin-1-yl)phenyl]-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-{4-[(4-cyclopropylpiperazin-1-yl)methyl]phenyl}-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(2-hydroxypyridin-4-yl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(4-cyclopropylpiperazin-1-yl)piperidin-1-yl]-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(9-cyclopropyl-3,9-diazaspiro[5.5]undecan-3-yl)-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[(pyrrolidin-1-yl)methyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-[2-(difluoromethoxy)pyridin-4-yl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[9-(propan-2-yl)-3,9-diazaspiro[5.5]undecan-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid -   3-cyclobutyl-4-{4-[4-(ethoxycarbonyl)piperazin-1-yl]piperidin-1-yl}-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-(4-methoxy[1,4′-bipiperidin]-1′-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-{[4-(morpholin-4-yl)piperidin-1-yl]methyl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(9-cyclobutyl-3,9-diazaspiro[5.5]undecan-3-yl)-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[(2-methoxyethyl)(methyl)amino]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[4-(2-methoxyethyl)piperazin-1-yl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[9-(2-methoxyethyl)-3,9-diazaspiro[5.5]undecan-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-(4-hydroxy[1,4′-bipiperidin]-1′-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[4-(oxetan-3-yl)piperazin-1-yl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[1-(propan-2-yl)octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-(1-cyclobutyloctahydro-5H-pyrrolo[3,2-c]pyridin-5-yl)-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[1-(oxetan-3-yl)octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[1-(oxan-4-yl)octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-[9-(oxetan-3-yl)-3,9-diazaspiro[5.5]undecan-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(3,5-difluorophenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(2,2-difluoro-2H-1,3-benzodioxol-5-yl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(3,4-difluorophenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluoro-3-methoxyphenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-[4-(trifluoromethoxy)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-[3-(difluoromethoxy)phenyl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(bicyclo[4.2.0]octa-1,3,5-trien-3-yl)-3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(3-fluoro-4-methoxyphenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(3-fluoro-5-methoxyphenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-[4-(difluoromethoxy)phenyl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-[3-(1,1-difluoroethyl)phenyl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(2,5-difluorophenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-[6-(2-fluoroethoxy)pyridin-3-yl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-{2-[(oxan-4-yl)oxy]pyridin-4-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-{2-[(oxan-4-yl)methoxy]pyridin-4-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(2,4-difluorophenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(2,2-difluoro-2H-1,3-benzodioxol-4-yl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   4-(4-cyanophenyl)-1-cyclohexyl-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-{6-[(propan-2-yl)oxy]pyridin-2-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-3-hydroxy-4-(4-methoxy[1,4′-bipiperidin]-1′-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-(4-fluorophenyl)-4-(4-methoxy[1,4′-bipiperidin]-1′-yl)-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   1-cyclohexyl-4-(4-{[3-(dimethylamino)azetidin-1-yl]methyl}phenyl)-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-1-(4-fluorophenyl)-4-(9-methyl-3,9-diazaspiro[5.5]undecan-3-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; -   3-cyclobutyl-4-[4-(ethoxycarbonyl)piperazin-1-yl]-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid; and -   3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[(2-methylpropoxy)carbonyl]piperazin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic     acid.

Compounds of the invention are named by using Name 2015 naming algorithm by Advanced Chemical Development, Struct=Name naming algorithm as part of CHEMDRAW® ULTRA v. 12.0.2.1076, or Accelrys Draw 4.2.

Compounds of the invention may exist as stereoisomers wherein asymmetric or chiral centers are present. These stereoisomers are “R” or “S” depending on the configuration of sub stituents around the chiral carbon atom. The terms “R” and “S” used herein are configurations as defined in IUPAC 1974 Recommendations for Section E, Fundamental Stereochemistry, in Pure Appl. Chem., 1976, 45: 13-30. The invention contemplates various stereoisomers and mixtures thereof and these are specifically included within the scope of this invention. Stereoisomers include enantiomers and diastereomers, and mixtures of enantiomers or diastereomers. Individual stereoisomers of compounds of the invention may be prepared synthetically from commercially available starting materials which contain asymmetric or chiral centers or by preparation of racemic mixtures followed by methods of resolution well-known to those of ordinary skill in the art. These methods of resolution are exemplified by (1) attachment of a mixture of enantiomers to a chiral auxiliary, separation of the resulting mixture of diastereomers by recrystallization or chromatography and optional liberation of the optically pure product from the auxiliary as described in Furniss, Hannaford, Smith, and Tatchell, “Vogel's Textbook of Practical Organic Chemistry”, 5th edition (1989), Longman Scientific & Technical, Essex CM20 2JE, England, or (2) direct separation of the mixture of optical enantiomers on chiral chromatographic columns or (3) fractional recrystallization methods.

Compounds of the invention may exist as cis or trans isomers, wherein substituents on a ring may attached in such a manner that they are on the same side of the ring (cis) relative to each other, or on opposite sides of the ring relative to each other (trans). For example, cyclobutane may be present in the cis or trans configuration, and may be present as a single isomer or a mixture of the cis and trans isomers. Individual cis or trans isomers of compounds of the invention may be prepared synthetically from commercially available starting materials using selective organic transformations, or prepared in single isomeric form by purification of mixtures of the cis and trans isomers. Such methods are well-known to those of ordinary skill in the art, and may include separation of isomers by recrystallization or chromatography.

It should be understood that the compounds of the invention may possess tautomeric forms, as well as geometric isomers, and that these also constitute an aspect of the invention.

The present disclosure includes all pharmaceutically acceptable isotopically-labelled compounds of formula (I) wherein one or more atoms are replaced by atoms having the same atomic number, but an atomic mass or mass number different from the atomic mass or mass number which predominates in nature. Examples of isotopes suitable for inclusion in the compounds of the disclosure include isotopes of hydrogen, such as ²H and ³H, carbon, such as ¹¹C, ¹³C and ¹⁴C, chlorine, such as ³⁶Cl, fluorine, such as ¹⁸F, iodine, such as ¹²³I and ¹²⁵I, nitrogen, such as ¹³N and ¹⁵N, oxygen, such as ¹⁵O, ¹⁷O and ¹⁸O, phosphorus, such as ³²P, and sulphur, such as ³⁵S. Certain isotopically-labelled compounds of formula (I), for example, those incorporating a radioactive isotope, are useful in drug and/or substrate tissue distribution studies. The radioactive isotopes tritium, i.e. ³H, and carbon-14, i.e. ¹⁴C, are particularly useful for this purpose in view of their ease of incorporation and ready means of detection. Substitution with heavier isotopes such as deuterium, i.e. ²H, may afford certain therapeutic advantages resulting from greater metabolic stability, for example, increased in vivo half-life or reduced dosage requirements, and hence may be preferred in some circumstances. Substitution with positron emitting isotopes, such as ¹¹C, ¹⁸F, ¹⁵O and ¹³N, can be useful in Positron Emission Topography (PET) studies for examining substrate receptor occupancy. Isotopically-labeled compounds of formula (I) may generally be prepared by conventional techniques known to those skilled in the art or by processes analogous to those described in the accompanying Examples using an appropriate isotopically-labeled reagents in place of the non-labeled reagent previously employed.

Thus, the formula drawings within this specification can represent only one of the possible tautomeric, geometric, or stereoisomeric forms. It is to be understood that the invention encompasses any tautomeric, geometric, or stereoisomeric form, and mixtures thereof, and is not to be limited merely to any one tautomeric, geometric, or stereoisomeric form utilized within the formula drawings.

Compounds of formula (I) may be used in the form of pharmaceutically acceptable salts. The phrase “pharmaceutically acceptable salt” means those salts which are, within the scope of sound medical judgement, suitable for use in contact with the tissues of humans and lower animals without undue toxicity, irritation, allergic response and the like and are commensurate with a reasonable benefit/risk ratio.

Pharmaceutically acceptable salts have been described in S. M. Berge et al. J. Pharmaceutical Sciences, 1977, 66: 1-19.

Compounds of formula (I) may contain either a basic or an acidic functionality, or both, and can be converted to a pharmaceutically acceptable salt, when desired, by using a suitable acid or base. The salts may be prepared in situ during the final isolation and purification of the compounds of the invention.

Examples of acid addition salts include, but are not limited to acetate, adipate, alginate, citrate, aspartate, benzoate, benzenesulfonate, bisulfate, butyrate, camphorate, camphorsulfonate, digluconate, glycerophosphate, hemisulfate, heptanoate, hexanoate, fumarate, hydrochloride, hydrobromide, hydroiodide, 2-hydroxyethansulfonate (isothionate), lactate, malate, maleate, methanesulfonate, nicotinate, 2-naphthalenesulfonate, oxalate, palmitoate, pectinate, persulfate, 3-phenylpropionate, picrate, pivalate, propionate, succinate, tartrate, thiocyanate, phosphate, glutamate, bicarbonate, p-toluenesulfonate and undecanoate. Also, the basic nitrogen-containing groups may be quaternized with such agents as lower alkyl halides such as, but not limited to, methyl, ethyl, propyl, and butyl chlorides, bromides and iodides; dialkyl sulfates like dimethyl, diethyl, dibutyl and diamyl sulfates; long chain halides such as, but not limited to, decyl, lauryl, myristyl and stearyl chlorides, bromides and iodides; arylalkyl halides like benzyl and phenethyl bromides and others. Water or oil-soluble or dispersible products are thereby obtained. Examples of acids which may be employed to form pharmaceutically acceptable acid addition salts include such inorganic acids as hydrochloric acid, hydrobromic acid, sulfuric acid, and phosphoric acid and such organic acids as acetic acid, fumaric acid, maleic acid, 4-methylbenzenesulfonic acid, succinic acid, and citric acid.

Basic addition salts may be prepared in situ during the final isolation and purification of compounds of this invention by reacting a carboxylic acid-containing moiety with a suitable base such as, but not limited to, the hydroxide, carbonate or bicarbonate of a pharmaceutically acceptable metal cation or with ammonia or an organic primary, secondary or tertiary amine. Pharmaceutically acceptable salts include, but are not limited to, cations based on alkali metals or alkaline earth metals such as, but not limited to, lithium, sodium, potassium, calcium, magnesium and aluminum salts and the like and nontoxic quaternary ammonia and amine cations including ammonium, tetramethylammonium, tetraethylammonium, methylamine, dimethylamine, trimethylamine, triethylamine, diethylamine, ethylamine and the like. Other examples of organic amines useful for the formation of base addition salts include ethylenediamine, ethanolamine, diethanolamine, piperidine, piperazine and the like.

The term “pharmaceutically acceptable prodrug” or “prodrug” as used herein, refers to derivatives of the compounds of the invention which have cleavable groups. Such derivatives become, by solvolysis or under physiological conditions, the compounds of the invention which are pharmaceutically active in vivo. Prodrugs of the compounds of the invention are, within the scope of sound medical judgement, suitable for use in contact with the tissues of humans and lower animals without undue toxicity, irritation, allergic response, and the like, commensurate with a reasonable benefit/risk ratio, and effective for their intended use.

The invention contemplates compounds of formula (I) formed by synthetic means or formed by in vivo biotransformation of a prodrug.

Compounds described herein may exist in unsolvated as well as solvated forms, including hydrated forms, such as hemi-hydrates. In general, the solvated forms, with pharmaceutically acceptable solvents such as water and ethanol among others are equivalent to the unsolvated forms for the purposes of the invention.

Pharmaceutical Compositions

When employed as a pharmaceutical, a compound of the invention is typically administered in the form of a pharmaceutical composition. Such compositions can be prepared in a manner well known in the pharmaceutical art and comprise a therapeutically effective amount of a compound of formula (I), or a pharmaceutically acceptable salt thereof together with a pharmaceutically acceptable carrier. The phrase “pharmaceutical composition” refers to a composition suitable for administration in medical or veterinary use.

The pharmaceutical compositions that comprise a compound of formula (I), alone or in combination with further therapeutically active ingredient, may be administered to the subjects orally, rectally, parenterally, intracisternally, intravaginally, intraperitoneally, topically (as by powders, ointments or drops), bucally or as an oral or nasal spray. The term “parenterally” as used herein, refers to modes of administration which include intravenous, intramuscular, intraperitoneal, intrasternal, subcutaneous and intraarticular injection and infusion.

The term “pharmaceutically acceptable carrier” as used herein, means a non-toxic, inert solid, semi-solid or liquid filler, diluent, encapsulating material or formulation auxiliary of any type. Some examples of materials which may serve as pharmaceutically acceptable carriers are sugars such as, but not limited to, lactose, glucose and sucrose; starches such as, but not limited to, corn starch and potato starch; cellulose and its derivatives such as, but not limited to, sodium carboxymethyl cellulose, ethyl cellulose and cellulose acetate; powdered tragacanth; malt; gelatin; talc; excipients such as, but not limited to, cocoa butter and suppository waxes; oils such as, but not limited to, peanut oil, cottonseed oil, safflower oil, sesame oil, olive oil, corn oil and soybean oil; glycols; such a propylene glycol; esters such as, but not limited to, ethyl oleate and ethyl laurate; agar; buffering agents such as, but not limited to, magnesium hydroxide and aluminum hydroxide; alginic acid; pyrogen-free water; isotonic saline; Ringer's solution; ethyl alcohol, and phosphate buffer solutions, as well as other non-toxic compatible lubricants such as, but not limited to, sodium lauryl sulfate and magnesium stearate, as well as coloring agents, releasing agents, coating agents, sweetening, flavoring and perfuming agents, preservatives and antioxidants may also be present in the composition, according to the judgment of the formulator.

Pharmaceutical compositions for parenteral injection comprise pharmaceutically acceptable sterile aqueous or nonaqueous solutions, dispersions, suspensions or emulsions as well as sterile powders for reconstitution into sterile injectable solutions or dispersions just prior to use. Examples of suitable aqueous and nonaqueous diluents, solvents, or vehicles include water, ethanol, polyols (such as glycerol, propylene glycol, polyethylene glycol and the like), vegetable oils (such as olive oil), injectable organic esters (such as ethyl oleate), and suitable mixtures thereof. Proper fluidity may be maintained, for example, by the use of coating materials such as lecithin, by the maintenance of the required particle size in the case of dispersions and by the use of surfactants.

These compositions may also contain adjuvants such as preservatives, wetting agents, emulsifying agents and dispersing agents. Prevention of the action of microorganisms may be ensured by the inclusion of various antibacterial and antifungal agents, for example, paraben, chlorobutanol, phenol sorbic acid, and the like. It may also be desirable to include isotonic agents such as sugars, sodium chloride, and the like. Prolonged absorption of the injectable pharmaceutical form may be brought about by the inclusion of agents which delay absorption, such as aluminum monostearate and gelatin.

In some cases, in order to prolong the effect of the drug, it may be desirable to slow the absorption of the drug from subcutaneous or intramuscular injection. This may be accomplished by the use of a liquid suspension of crystalline or amorphous material with poor water solubility. The rate of absorption of the drug then depends upon its rate of dissolution which, in turn, may depend upon crystal size and crystalline form. Alternatively, delayed absorption of a parenterally-administered drug form may be accomplished by dissolving or suspending the drug in an oil vehicle.

Injectable depot forms are made by forming microencapsule matrices of the drug in biodegradable polymers such as polylactide-polyglycolide. Depending upon the ratio of drug to polymer and the nature of the particular polymer employed, the rate of drug release may be controlled. Examples of other biodegradable polymers include poly(orthoesters) and poly(anhydrides). Depot injectable formulations are also prepared by entrapping the drug in liposomes or microemulsions which are compatible with body tissues.

The injectable formulations may be sterilized, for example, by filtration through a bacterial-retaining filter or by incorporating sterilizing agents in the form of sterile solid compositions which can be dissolved or dispersed in sterile water or other sterile injectable medium just prior to use.

Solid dosage forms for oral administration include capsules, tablets, pills, powders, and granules. In certain embodiments, solid dosage forms may contain from 1% to 95% (w/w) of a compound of formula (I). In certain embodiments, the compound of formula (I), or pharmaceutically acceptable salts thereof, may be present in the solid dosage form in a range of from 5% to 70% (w/w). In such solid dosage forms, the active compound may be mixed with at least one inert, pharmaceutically acceptable carrier, such as sodium citrate or dicalcium phosphate and/or a), fillers or extenders such as starches, lactose, sucrose, glucose, mannitol, and silicic acid; b) binders such as carboxymethylcellulose, alginates, gelatin, polyvinylpyrrolidone, sucrose, and acacia; c) humectants such as glycerol; d) disintegrating agents such as agar-agar, calcium carbonate, potato or tapioca starch, alginic acid, certain silicates, and sodium carbonate; e) solution retarding agents such as paraffin; f) absorption accelerators such as quaternary ammonium compounds; g) wetting agents such as cetyl alcohol and glycerol monostearate; h) absorbents such as kaolin and bentonite clay and i) lubricants such as talc, calcium stearate, magnesium stearate, solid polyethylene glycols, sodium lauryl sulfate and mixtures thereof. In the case of capsules, tablets and pills, the dosage form may also comprise buffering agents.

The pharmaceutical composition may be a unit dosage form. In such form the preparation is subdivided into unit doses containing appropriate quantities of the active component. The unit dosage form can be a packaged preparation, the package containing discrete quantities of preparation, such as packeted tablets, capsules, and powders in vials or ampules. Also, the unit dosage form may be a capsule, tablet, cachet, or lozenge itself, or it may be the appropriate number of any of these in packaged form. The quantity of active component in a unit dose preparation may be varied or adjusted from 0.1 mg to 1000 mg, from 1 mg to 100 mg, or from 1% to 95% (w/w) of a unit dose, according to the particular application and the potency of the active component. The composition may, if desired, also contain other compatible therapeutic agents.

The dose to be administered to a subject may be determined by the efficacy of the particular compound employed and the condition of the subject, as well as the body weight or surface area of the subject to be treated. The size of the dose also will be determined by the existence, nature, and extent of any adverse side-effects that accompany the administration of a particular compound in a particular subject. In determining the effective amount of the compound to be administered in the treatment or prophylaxis of the disorder being treated, the physician may evaluate factors such as the circulating plasma levels of the compound, compound toxicities, and/or the progression of the disease, etc.

For administration, compounds may be administered at a rate determined by factors that may include, but are not limited to, the LD₅₀ of the compound, the pharmacokinetic profile of the compound, contraindicated drugs, and the side-effects of the compound at various concentrations, as applied to the mass and overall health of the subject. Administration may be accomplished via single or divided doses.

The compounds utilized in the pharmaceutical method of the invention may be administered at the initial dosage of about 0.001 mg/kg to about 100 mg/kg daily. In certain embodiments, the daily dose range is from about 0.1 mg/kg to about 10 mg/kg. The dosages, however, may be varied depending upon the requirements of the subject, the severity of the condition being treated, and the compound being employed. Determination of the proper dosage for a particular situation is within the skill of the practitioner. Treatment may be initiated with smaller dosages, which are less than the optimum dose of the compound. Thereafter, the dosage is increased by small increments until the optimum effect under circumstances is reached. For convenience, the total daily dosage may be divided and administered in portions during the day, if desired.

Solid compositions of a similar type may also be employed as fillers in soft and hard-filled gelatin capsules using such carriers as lactose or milk sugar as well as high molecular weight polyethylene glycols and the like.

The solid dosage forms of tablets, dragees, capsules, pills and granules can be prepared with coatings and shells such as enteric coatings and other coatings well-known in the pharmaceutical formulating art. They may optionally contain opacifying agents and may also be of a composition such that they release the active ingredient(s) only, or preferentially, in a certain part of the intestinal tract, optionally, in a delayed manner. Examples of embedding compositions which can be used include polymeric substances and waxes.

The active compounds may also be in micro-encapsulated form, if appropriate, with one or more of the above-mentioned carriers.

Liquid dosage forms for oral administration include pharmaceutically acceptable emulsions, solutions, suspensions, syrups and elixirs. In addition to the active compounds, the liquid dosage forms may contain inert diluents commonly used in the art such as, for example, water or other solvents, solubilizing agents and emulsifiers such as ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1,3-butylene glycol, dimethyl formamide, oils (in particular, cottonseed, groundnut, corn, germ, olive, castor and sesame oils), glycerol, tetrahydrofurfuryl alcohol, polyethylene glycols, and fatty acid esters of sorbitan and mixtures thereof.

Besides inert diluents, the oral compositions may also include adjuvants such as wetting agents, emulsifying and suspending agents, sweetening, flavoring and perfuming agents.

Suspensions, in addition to the active compounds, may contain suspending agents as, for example, ethoxylated isostearyl alcohols, polyoxyethylene sorbitol and sorbitan esters, microcrystalline cellulose, aluminum metahydroxide, bentonite, agar-agar, tragacanth and mixtures thereof.

Compositions for rectal or vaginal administration are preferably suppositories which may be prepared by mixing the compounds with suitable non-irritating carriers or carriers such as cocoa butter, polyethylene glycol, or a suppository wax which are solid at room temperature but liquid at body temperature and therefore melt in the rectum or vaginal cavity and release the active compound.

Compounds may also be administered in the form of liposomes. Liposomes generally may be derived from phospholipids or other lipid substances. Liposomes are formed by mono- or multi-lamellar hydrated liquid crystals which are dispersed in an aqueous medium. Any non-toxic, physiologically acceptable and metabolizable lipid capable of forming liposomes may be used. The present compositions in liposome form may contain, in addition to a compound of the invention, stabilizers, preservatives, excipients, and the like. Examples of lipids include, but are not limited to, natural and synthetic phospholipids, and phosphatidyl cholines (lecithins), used separately or together.

Methods to form liposomes have been described, see example, Prescott, Ed., Methods in Cell Biology, Volume XIV, Academic Press, New York, N.Y. (1976), p. 33 et seq.

Dosage forms for topical administration of a compound described herein include powders, sprays, ointments, and inhalants. The active compound may be mixed under sterile conditions with a pharmaceutically acceptable carrier and any needed preservatives, buffers or propellants which may be required. Opthalmic formulations, eye ointments, powders and solutions are also contemplated as being within the scope of this invention.

A compound of the invention may also be administered in sustained release forms or from sustained release drug delivery systems.

Methods of Use

The compounds and compositions using any amount and any route of administration may be administered to a subject for the treatment or prevention of cystic fibrosis, pancreatic insufficiency, Sjögren's Syndrome (SS), chronic obstructive lung disease (COLD), or chronic obstructive airway disease (COAD).

The term “administering” refers to the method of contacting a compound with a subject. Thus, the compounds may be administered by injection, that is, intravenously, intramuscularly, intracutaneously, subcutaneously, intraduodenally, parentally, or intraperitoneally. Also, the compounds described herein may be administered by inhalation, for example, intranasally. Additionally, the compounds may be administered transdermally, topically, and via implantation. In certain embodiments, the compounds and compositions thereof may be delivered orally. The compounds may also be delivered rectally, bucally, intravaginally, ocularly, or by insufflation. CFTR-modulated disorders and conditions may be treated prophylactically, acutely, and chronically using compounds and compositions thereof, depending on the nature of the disorder or condition. Typically, the host or subject in each of these methods is human, although other mammals may also benefit from the administration of compounds and compositions thereof as set forth hereinabove.

Compounds of the invention are useful as modulators of CFTR. Thus, the compounds and compositions are particularly useful for treating or lessening the severity or progression of a disease, disorder, or a condition where hyperactivity or inactivity of CFTR is involved. Accordingly, the invention provides a method for treating cystic fibrosis, pancreatic insufficiency, Sjögren's Syndrome (SS), chronic obstructive lung disease (COLD), or chronic obstructive airway disease (COAD) in a subject, wherein the method comprises the step of administering to said subject a therapeutically effective amount of a compound of formula (I) or a preferred embodiment thereof as set forth above, with or without a pharmaceutically acceptable carrier. Particularly, the method is for the treatment or prevention of cystic fibrosis. In a more particular embodiment, the cystic fibrosis is caused by a Class I, II, III, IV, V, and/or VI mutation.

In another embodiment, the present invention provides compounds of the invention, or pharmaceutical compositions comprising a compound of the invention for use in medicine. In a particular embodiment, the present invention provides compounds of the invention or pharmaceutical compositions comprising a compound of the invention, for use in the treatment of cystic fibrosis, pancreatic insufficiency, Sjögren's Syndrome (SS), chronic obstructive lung disease (COLD) or chronic obstructive airway disease (COAD). In a more particular embodiment, the present invention provides compounds of the invention or pharmaceutical compositions comprising a compound of the invention, for use in the treatment of cystic fibrosis. In a more particular embodiment, the cystic fibrosis is caused by a Class I, II, III, IV, V, and/or VI mutation.

One embodiment is directed to the use of a compound according to formula (I) or a pharmaceutically acceptable salt thereof in the preparation of a medicament. The medicament optionally can comprise one or more additional therapeutic agents. In some embodiments, the medicament is for use in the treatment of cystic fibrosis, pancreatic insufficiency, Sjögren's Syndrome (SS), chronic obstructive lung disease (COLD) or chronic obstructive airway disease (COAD). In a particular embodiment, the medicament is for use in the treatment of cystic fibrosis. In a more particular embodiment, the cystic fibrosis is caused by a Class I, II, III, IV, V, and/or VI mutation.

This invention also is directed to the use of a compound according to formula (I) or a pharmaceutically acceptable salt thereof in the manufacture of a medicament for the treatment of cystic fibrosis, Sjögren's syndrome, pancreatic insufficiency, chronic obstructive lung disease, and chronic obstructive airway disease. The medicament optionally can comprise one or more additional therapeutic agents. In a particular embodiment, the invention is directed to the use of a compound according to formula (I) or a pharmaceutically acceptable salt thereof in the manufacture of a medicament for the treatment of cystic fibrosis. In a more particular embodiment, the cystic fibrosis is caused by a Class I, II, III, IV, V, and/or VI mutation.

In one embodiment, the present invention provides pharmaceutical compositions comprising a compound of the invention or a pharmaceutically acceptable salt thereof, and one or more additional therapeutic agents. In a particular embodiment, the other therapeutic agent is a cystic fibrosis treatment agent. In a more particular embodiment, the cystic fibrosis is caused by a Class I, II, III, IV, V, and/or VI mutation.

The present compounds or pharmaceutically acceptable salts thereof may be administered as the sole active agent or it may be co-administered with other therapeutic agents, including other compounds or pharmaceutically acceptable salts thereof that demonstrate the same or a similar therapeutic activity and that are determined to be safe and efficacious for such combined administration. The term “co-administered” means the administration of two or more different therapeutic agents to a subject in a single pharmaceutical composition or in separate pharmaceutical compositions. Thus co-administration involves administration at the same time of a single pharmaceutical composition comprising two or more therapeutic agents or administration of two or more different compositions to the same subject at the same or different times.

The compounds of the invention or pharmaceutically acceptable salts thereof may be co-administered with a therapeutically effective amount of one or more additional therapeutic agents to treat a CFTR mediated disease, where examples of the therapeutic agents include, but are not limited to antibiotics (for example, aminoglycosides, colistin, aztreonam, ciprofloxacin, and azithromycin), expectorants (for example, hypertonic saline, acetylcysteine, dornase alfa, and denufosol), pancreatic enzyme supplements (for example, pancreatin, and pancrelipase), epithelial sodium channel blocker (ENaC) inhibitors, CFTR modulators (for example, CFTR potentiators, CFTR correctors), and CFTR amplifiers. In one embodiment, the CFTR mediated disease is cystic fibrosis, chronic obstructive pulmonary disease (COPD), dry eye disease, pancreatic insufficiency, or Sjogren's syndrome. In one embodiment, the CFTR mediated disease is cystic fibrosis. In one embodiment, the CFTR mediated disease is cystic fibrosis. In one embodiment, the compounds of the invention or pharmaceutically acceptable salts thereof may be co-administered with one or two CFTR modulators and one CFTR amplifier. In one embodiment, the compounds of the invention or pharmaceutically acceptable salts thereof may be co-administered with one potentiator, one or more correctors, and one CFTR amplifier. In one embodiment, the compounds of the invention or pharmaceutically acceptable salts thereof may be co-administered with one or more CFTR modulators. In one embodiment, the compounds of the invention or pharmaceutically acceptable salts thereof may be co-administered with one CFTR modulators. In one embodiment, the compounds of the invention or pharmaceutically acceptable salts thereof may be co-administered with two CFTR modulators. In one embodiment, the compounds of the invention or pharmaceutically acceptable salts thereof may be co-administered with three CFTR modulators. In one embodiment, the compounds of the invention or pharmaceutically acceptable salts thereof may be co-administered with one potentiator and one or more correctors. In one embodiment, the compounds of the invention or pharmaceutically acceptable salts thereof may be co-administered with one potentiator and one corrector. In one embodiment, the compounds of the invention or pharmaceutically acceptable salts thereof may be co-administered with one potentiator and two correctors. In one embodiment, the compounds of the invention or pharmaceutically acceptable salts thereof may be co-administered with one potentiator. In one embodiment, the compounds of the invention or pharmaceutically acceptable salts thereof may be co-administered with one or more correctors. In one embodiment, the compounds of the invention or pharmaceutically acceptable salts thereof may be co-administered with one corrector. In one embodiment, the compounds of the invention or pharmaceutically acceptable salts thereof may be co-administered with two correctors.

Examples of CFTR potentiators include, but are not limited to, Ivacaftor (VX-770), CTP-656, NVS-QBW251, FD1860293, PTI-808, GLPG2451, GLPG1837, and N-(3-carbamoyl-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-2-yl)-1H-pyrazole-5-carboxamide. Examples of potentiators are also disclosed in publications: WO2005120497, WO2008147952, WO2009076593, WO2010048573, WO2006002421, WO2011072241, WO2011113894, WO2013038373, WO2013038378, WO2013038381, WO2013038386, WO2013038390, WO2014180562, WO2015018823; and U.S. application Ser. Nos. 14/271,080, 14/451,619, and 15/164,317.

In one embodiment, the potentiator can be selected from the group consisting of:

-   Ivacaftor (VX-770,     N-(2,4-di-tert-butyl-5-hydroxyphenyl)-4-oxo-1,4-dihydroquinoline-3-carboxamide); -   CTP-656; -   NVS-QBW251, -   FD1860293; -   PTI-808; -   GLPG1837; -   GLPG2451; -   2-(2-fluorobenzamido)-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carboxamide; -   N-(3-carbamoyl-5,5,7,7-tetramethyl-4,7-dihydro-5H-thieno[2,3-c]pyran-2-yl)-1H-pyrazole-5-carboxamide; -   2-(2-hydroxybenzamido)-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carboxamide; -   2-(1-hydroxycyclopropanecarboxamido)-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carboxamide; -   5,5,7,7-tetramethyl-2-(2-(trifluoromethyl)benzamido)-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carboxamide; -   2-(2-hydroxy-2-methylpropanamido)-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carboxamide; -   2-(1-(hydroxymethyl)cyclopropanecarboxamido)-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carboxamide; -   2-(3-hydroxy-2,2-dimethylpropanamido)-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carboxamide; -   N-(3-carbamoyl-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-2-yl)-5-methyl-1H-pyrazole-3-carboxamide; -   N-(3-carbamoyl-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-2-yl)-5-cyclopropyl-1H-pyrazole-3-carboxamide; -   N-(3-carbamoyl-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-2-yl)-5-isopropyl-1H-pyrazole-3-carboxamide; -   N-(3-carbamoyl-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-2-yl)-5-(trifluoromethyl)-1H-pyrazole-3-carboxamide; -   5-tert-butyl-N-(3-carbamoyl-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-2-yl)-1H-pyrazole-3-carboxamide; -   N-(3-carbamoyl-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-2-yl)-5-ethyl-1H-pyrazole-3-carboxamide; -   N-(3-carbamoyl-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-2-yl)-3-ethyl-4-methyl-1H-pyrazole-5-carboxamide; -   2-(2-hydroxypropanamido)-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carboxamide; -   N-(3-carbamoyl-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-2-yl)-4-chloro-1H-pyrazole-3-carboxamide; -   N-(3-carbamoyl-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-2-yl)-1,4,6,7-tetrahydropyrano[4,3-c]pyrazole-3-carboxamide; -   4-bromo-N-(3-carbamoyl-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-2-yl)-1H-pyrazole-3-carboxamide; -   N-(3-carbamoyl-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-2-yl)-4-chloro-5-methyl-1H-pyrazole-3-carboxamide; -   N-(3-carbamoyl-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-2-yl)-4-methyl-1H-pyrazole-3-carboxamide; -   2-(2-hydroxy-3,3-dimethylbutanamido)-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-3-carboxamide; -   2-[(2-hydroxy-4-methyl-pentanoyl)amino]-5,5,7,7-tetramethyl-4H-thieno[2,3-c]pyran-3-carboxamide; -   5-(2-methoxy-ethoxy)-1H-pyrazole-3-carboxylic acid     (3-carbamoyl-5,5,7,7-tetramethyl-4,7-dihydro-5H-thieno[2,3-c]pyran-2-yl)-amide; -   N-(3-carbamoyl-5,5,7,7-tetramethyl-4H-thieno[2,3-c]pyran-2-yl)-4-(3-methoxypropyl)-1H-pyrazole-3-carboxamide; -   N-(3-carbamoyl-5,5,7,7-tetramethyl-4H-thieno[2,3-c]pyran-2-yl)-4-(2-ethoxyethyl)-1H-pyrazole-3-carboxamide; -   2-[[(2S)-2-hydroxy-3,3-dimethyl-butanoyl]amino]-5,5,7,7-tetramethyl-4H-thieno[2,3-c]pyran-3-carboxamide; -   2-[[(2R)-2-hydroxy-3,3-dimethyl-butanoyl]amino]-5,5,7,7-tetramethyl-4H-thieno[2,3-c]pyran-3-carboxamide; -   2-[(2-hydroxy-2,3,3-trimethyl-butanoyl)amino]-5,5,7,7-tetramethyl-4H-thieno[2,3-c]pyran-3-carboxamide; -   [5-[(3-carbamoyl-5,5,7,7-tetramethyl-4H-thieno[2,3-c]pyran-2-yl)carbamoyl]pyrazol-1-yl]methyl     dihydrogen phosphate; -   [3-[(3-carbamoyl-5,5,7,7-tetramethyl-4H-thieno[2,3-c]pyran-2-yl)carbamoyl]pyrazol-1-yl]methyl     dihydrogen phosphate; -   N-(3-carbamoyl-5,5,7,7-tetramethyl-4H-thieno[2,3-c]pyran-2-yl)-4-(1,4-dioxan-2-yl)-1H-pyrazole-3-carboxamide; -   5,5,7,7-tetramethyl-2-[[(2S)-3,3,3-trifluoro-2-hydroxy-2-methyl-propanoyl]amino]-4H-thieno[2,3-c]pyran-3-carboxamide; -   2-[[(2S)-2-hydroxypropanoyl]amino]-5,5,7,7-tetramethyl-4H-thieno[2,3-c]pyran-3-carboxamide; -   3-amino-N-(2-hydroxy-2-methylpropyl)-5-{[4-(trifluoromethoxy)phenyl]sulfonyl}pyridine-2-carboxamide; -   3-amino-N-[(4-hydroxy-1-methylpiperidin-4-yl)methyl]-5-{[4-(trifluoromethoxy)phenyl]sulfonyl}pyridine-2-carboxamide; -   3-amino-N-(3-hydroxy-2,2-dimethylpropyl)-5-{[4-(trifluoromethoxy)phenyl]sulfonyl}pyridine-2-carboxamide; -   3-amino-5-[(4-fluorophenyl)sulfonyl]-N-[(1-hydroxycyclopropyl)methyl]pyridine-2-carboxamide; -   3-amino-5-[(4-fluorophenyl)sulfonyl]-N-[(2R)-3,3,3-trifluoro-2-hydroxypropyl]pyridine-2-carboxamide; -   3-amino-5-[(3-fluorophenyl)sulfonyl]-N-(2-hydroxy-2-methylpropyl)pyridine-2-carboxamide; -   3-amino-N-[2-(cyclopropylamino)-2-oxoethyl]-5-{[4-(trifluoromethoxy)phenyl]sulfonyl}pyridine-2-carboxamide; -   (3-amino-5-{[4-(trifluoromethoxy)phenyl]sulfonyl}pyridin-2-yl)(azetidin-1-yl)methanone; -   (3-amino-5-{[4-(trifluoromethoxy)phenyl]sulfonyl}pyridin-2-yl)[3-(hydroxymethyl)azetidin-1-yl]methanone; -   (3-amino-5-{[4-(trifluoromethoxy)phenyl]sulfonyl}pyridin-2-yl)(3-fluoroazetidin-1-yl)methanone; -   3-amino-N-[(2R)-2-hydroxy-3-methoxypropyl]-5-{[4-(trifluoromethyl)phenyl]sulfonyl}pyridine-2-carboxamide; -   (3-amino-5-{[2-fluoro-4-(trifluoromethoxy)phenyl]sulfonyl}pyridin-2-yl)(3-hydroxyazetidin-1-yl)methanone; -   (3-amino-5-{[2-(trifluoromethoxy)phenyl]sulfonyl}pyridin-2-yl)(3,3-difluoroazetidin-1-yl)methanone; -   rac-3-amino-N-[(3R,4S)-4-hydroxytetrahydro-2H-pyran-3-yl]-5-{[2-(trifluoromethoxy)phenyl]sulfonyl}pyridine-2-carboxamide; -   3-amino-5-[(4,4-difluoropiperidin-1-yl)sulfonyl]-N-(3,3,3-trifluoro-2-hydroxypropyl)pyridine-2-carboxamide; -   (3-amino-5-{[2-(trifluoromethoxy)phenyl]sulfonyl}pyridin-2-yl)[3-hydroxy-3-(trifluoromethyl)azetidin-1-yl]methanone; -   3-amino-N-(2-hydroxy-4-methylpentyl)-5-{[4-(trifluoromethoxy)phenyl]sulfonyl}pyridine-2-carboxamide; -   (3-amino-5-{[4-(trifluoromethyl)phenyl]sulfonyl}pyridin-2-yl)(3-hydroxy-3-methylazetidin-1-yl)methanone; -   3-amino-N-(3,3,3-trifluoro-2-hydroxypropyl)-5-{[4-(trifluoromethyl)piperidin-1-yl]sulfonyl}pyridine-2-carboxamide; -   3-amino-N-[2-hydroxy-1-(4-methoxyphenyl)ethyl]-5-{[4-(trifluoromethoxy)phenyl]sulfonyl}pyridine-2-carboxamide; -   3-amino-5-[(3,3-difluoroazetidin-1-yl)sulfonyl]-N-(3,3,3-trifluoro-2-hydroxypropyl)pyridine-2-carboxamide; -   3-amino-5-{[2-fluoro-4-(trifluoromethyl)phenyl]sulfonyl}-N-[(2S)-2-hydroxypropyl]pyridine-2-carboxamide; -   3-amino-5-{[2-fluoro-4-(trifluoromethyl)phenyl]sulfonyl}-N-[(2R)-2-hydroxy-3-methoxypropyl]pyridine-2-carboxamide; -   3-amino-N-[2-oxo-2-(propan-2-ylamino)ethyl]-5-{[4-(trifluoromethyl)phenyl]sulfonyl}pyridine-2-carboxamide; -   (3-amino-5-{[4-(trifluoromethyl)phenyl]sulfonyl}pyridin-2-yl)[3-hydroxy-3-(trifluoromethyl)azetidin-1-yl]methanone; -   3-amino-5-{[2-fluoro-4-(trifluoromethyl)phenyl]sulfonyl}-N-[(3R)-tetrahydrofuran-3-ylmethyl]pyridine-2-carboxamide; -   (3-amino-5-{[2-fluoro-4-(trifluoromethyl)phenyl]sulfonyl}pyridin-2-yl)[3-hydroxy-3-(trifluoromethyl)azetidin-1-yl]methanone; -   3-amino-5-{[2-fluoro-4-(trifluoromethyl)phenyl]sulfonyl}-N-[(3S)-tetrahydrofuran-3-ylmethyl]pyridine-2-carboxamide; -   3-amino-5-{[2-fluoro-4-(trifluoromethoxy)phenyl]sulfonyl}-N-[(3S)-tetrahydrofuran-3-ylmethyl]pyridine-2-carboxamide; -   3-amino-N-[2-hydroxy-3-(2,2,2-trifluoroethoxy)propyl]-5-{[4-(trifluoromethyl)phenyl]sulfonyl}pyridine-2-carboxamide; -   3-amino-N-(3-tert-butoxy-2-hydroxypropyl)-5-{[2-fluoro-4-(trifluoromethyl)phenyl]sulfonyl}pyridine-2-carboxamide; -   [3-amino-5-(phenylsulfonyl)pyridin-2-yl][3-hydroxy-3-(trifluoromethyl)azetidin-1-yl]methanone; -   {3-amino-5-[(3-fluorophenyl)sulfonyl]pyridin-2-yl}[3-hydroxy-3-(trifluoromethyl)azetidin-1-yl]methanone;     and -   3-amino-N-[(2S)-2-hydroxypropyl]-5-{[4-(trifluoromethoxy)phenyl]sulfonyl}pyridine-2-carboxamide.

Non-limiting examples of correctors include Lumacaftor (VX-809), 1-(2,2-difluoro-1,3-benzodioxol-5-yl)-N-{1-[(2R)-2,3-dihydroxypropyl]-6-fluoro-2-(1-hydroxy-2-methylpropan-2-yl)-1H-indol-5-yl}cyclopropanecarboxamide (VX-661), VX-983, GLPG2222, GLPG2665, GLPG2737, GLPG2851, VX-152, VX-440, FDL169, FDL304, FD2052160, and FD2035659. Examples of correctors are also disclosed in US20160095858A1, and U.S. application Ser. Nos. 14/925,649, 14/926,727, 15/205,512, 62/239,647, and 62/309,794.

In one embodiment, the corrector(s) can be selected from the group consisting of:

-   Lumacaftor (VX-809); -   1-(2,2-difluoro-1,3-benzodioxol-5-yl)-N-{1-[(2R)-2,3-dihydroxypropyl]-6-fluoro-2-(1-hydroxy-2-methylpropan-2-yl)-1H-indol-5-yl}cyclopropanecarboxamide     (VX-661); -   PTI-801; -   VX-983; -   VX-152; -   VX-440; -   FDL169 -   FDL304; -   FD2052160; -   FD2035659; -   GLPG2665; -   GLPG2737; -   GLPG2851; -   3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-methoxy-3,4-dihydro-2H-chromen-2-yl]benzoic     acid; -   3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-3,4-dihydro-2H-chromen-2-yl]benzoic     acid; -   3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-6-methyl-3,4-dihydro-2H-chromen-2-yl]benzoic     acid; -   3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-methyl-3,4-dihydro-2H-chromen-2-yl]benzoic     acid; -   3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-6-methoxy-3,4-dihydro-2H-chromen-2-yl]benzoic     acid; -   3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-(difluoromethoxy)-3,4-dihydro-2H-chromen-2-yl]cyclohexanecarboxylic     acid; -   3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-(difluoromethoxy)-3,4-dihydro-2H-chromen-2-yl]benzoic     acid; -   3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-methoxy-3,4-dihydro-2H-chromen-2-yl]cyclohexanecarboxylic     acid; -   3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-fluoro-3,4-dihydro-2H-chromen-2-yl]benzoic     acid; -   3-({3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-methyl-3,4-dihydro-2H-chromen-2-yl]benzoyl}amino)-1-methylcyclopentanecarboxylic     acid; -   3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-methyl-3,4-dihydro-2H-chromen-2-yl]-N-[(2R)-2,3-dihydroxypropyl]benzamide; -   3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-(2-methoxyethoxy)-3,4-dihydro-2H-chromen-2-yl]benzoic     acid; -   3-[(2R,4R)-7-(benzyloxy)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-3,4-dihydro-2H-chromen-2-yl]benzoic     acid; -   3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-(2-fluoroethoxy)-3,4-dihydro-2H-chromen-2-yl]benzoic     acid; -   3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-(trifluoromethyl)-3,4-dihydro-2H-chromen-2-yl]benzoic     acid; -   3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-(trifluoromethyl)-3,4-dihydro-2H-chromen-2-yl]cyclohexanecarboxylic     acid; -   4-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-methoxy-3,4-dihydro-2H-chromen-2-yl]benzoic     acid; -   3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-8-fluoro-3,4-dihydro-2H-chromen-2-yl]benzoic     acid; -   4-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-3,4-dihydro-2H-chromen-2-yl]benzoic     acid; -   4-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-(difluoromethoxy)-3,4-dihydro-2H-chromen-2-yl]benzoic     acid; -   rac-3-[(2R,4S)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)tetrahydro-2H-pyran-2-yl]benzoic     acid; -   rac-4-[(2R,4S)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)tetrahydro-2H-pyran-2-yl]benzoic     acid; -   3-[(2S,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)tetrahydro-2H-pyran-2-yl]benzoic     acid; -   3-[(2R,4S)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)tetrahydro-2H-pyran-2-yl]benzoic     acid; -   rac-3-[(2R,4S,6S)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-6-phenyhetrahydro-2H-pyran-2-yl]benzoic     acid; -   3-[(2S,4R,6R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-6-phenyhetrahydro-2H-pyran-2-yl]benzoic     acid; -   3-[(2R,4S,6S)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-6-phenyhetrahydro-2H-pyran-2-yl]benzoic     acid; -   4-[(2R,4S)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)tetrahydro-2H-pyran-2-yl]benzoic     acid; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-cyclobutyl-N-(methanesulfonyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carb     oxamide; -   3-cyclobutyl-N-(methanesulfonyl)-4-[4-(methoxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxamide; -   4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-cyclobutyl-N-(methanesulfonyl)-1-[2-(morpholin-4-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxamid; -   N-(methanesulfonyl)-4-[4-(methoxymethyl)piperidin-1-yl]-1-[2-(morpholin-4-yl)pyridin-4-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxamide; -   3-cyclobutyl-4-[4-(methoxymethyl)piperidin-1-yl]-N-[2-(morpholin-4-yl)ethanesulfonyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxamide; -   3-cyclobutyl-N-[2-(dimethylamino)ethanesulfonyl]-4-[4-(methoxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxamide; -   1-(4-fluorophenyl)-N-(methanesulfonyl)-4-(1′-methyl[4,4′-bipiperidin]-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxamide; -   3-cyclobutyl-N-(methanesulfonyl)-4-{4-[2-(morpholin-4-yl)ethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carb     oxamide; -   3-cyclobutyl-4-[4-(methoxymethyl)piperidin-1-yl]-N-(oxolane-3-sulfonyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxamide; -   3-cyclobutyl-N-(dimethyl     sulfamoyl)-1-(4-fluorophenyl)-4-(4-methoxy[1,4′-bipiperidin]-1′-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxamide; -   3-cyclobutyl-N-(morpholine-4-sulfonyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carb     oxamide; -   3-cyclobutyl-N-(morpholine-4-sulfonyl)-1-phenyl-4-{4-[(pyrrolidin-1-yl)methyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxamide;

3-cyclobutyl-N-(methanesulfonyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxamide;

-   5-[(2R,4R)-4-{[(7R)-2,2-difluoro-7-methyl-6,7-dihydro-2H-furo[2,3-f][1,3]benzodioxole-7-carbonyl]amino}-7-methoxy-3,4-dihydro-2H-1-benzopyran-2-yl]pyrazine-2-carboxylic     acid; -   6-[(2R,4R)-4-{[(7R)-2,2-difluoro-7-methyl-6,7-dihydro-2H-furo[2,3-f][1,3]benzodioxole-7-carbonyl]amino}-7-(trifluoromethoxy)-3,4-dihydro-2H-1-benzopyran-2-yl]pyridine-3-carboxylic     acid; -   trans-4-[(2S,4S)-4-{[(7R)-2,2-difluoro-7-methyl-6,7-dihydro-2H-furo[2,3-f][1,3]benzodioxole-7-carbonyl]amino}-7-(trifluoromethoxy)-3,4-dihydro-2H-1-benzopyran-2-yl]cyclohexane-1-carboxylic     acid; -   6-[(2R,4R)-7-(difluoromethoxy)-4-{[(7R)-2,2-difluoro-7-methyl-6,7-dihydro-2H-furo[2,3-f][1,3]benzodioxole-7-carbonyl]amino}-3,4-dihydro-2H-1-benzopyran-2-yl]pyridine-3-carboxylic     acid; -   trans-4-[(2S,4S)-4-{[(7R)-2,2-difluoro-7-methyl-6,7-dihydro-2H-furo[2,3-f][1,3]benzodioxole-7-carbonyl]amino}-7-methoxy-3,4-dihydro-2H-1-benzopyran-2-yl]cyclohexane-1-carboxylic     acid; -   ethyl     trans-4-[(2S,4S)-7-(difluoromethoxy)-4-{[(7R)-2,2-difluoro-7-methyl-6,7-dihydro-2H-furo[2,3-f][1,3]benzodioxole-7-carbonyl]amino}-3,4-dihydro-2H-1-benzopyran-2-yl]cyclohexane-1-carboxylate; -   cis-4-[(2R,4R)-4-{[(7R)-2,2-difluoro-7-methyl-6,7-dihydro-2H-furo[2,3-f][1,3]benzodioxole-7-carbonyl]amino}-7-(trifluoromethoxy)-3,4-dihydro-2H-1-benzopyran-2-yl]cyclohexane-1-carboxylic     acid; -   trans-4-[(2S,4S)-7-(difluoromethoxy)-4-{[(7R)-2,2-difluoro-7-methyl-6,7-dihydro-2H-furo[2,3-f][1,3]benzodioxole-7-carbonyl]amino}-3,4-dihydro-2H-1-benzopyran-2-yl]cyclohexane-1-carboxylic     acid; -   1-[(2R,4R)-4-{[(7R)-2,2-difluoro-7-methyl-6,7-dihydro-2H-furo[2,3-f][1,3]benzodioxole-7-carbonyl]amino}-7-(trifluoromethoxy)-3,4-dihydro-2H-1-benzopyran-2-yl]cyclopropane-1-carboxylic     acid; -   trans-4-[(2R,4R)-4-{[(5S)-2,2-difluoro-5-methyl-6,7-dihydro-2H,5H-indeno[5,6-d][1,3]dioxole-5-carbonyl]amino}-7-(trifluoromethoxy)-3,4-dihydro-2H-1-benzopyran-2-yl]cyclohexane-1-carboxylic     acid; -   trans-4-[(2R,4R)-4-{[(5S)-2,2-difluoro-5-methyl-6,7-dihydro-2H,5H-indeno[5,6-d][1,3]dioxole-5-carbonyl]amino}-7-methoxy-3,4-dihydro-2H-1-benzopyran-2-yl]cyclohexane-1-carboxylic     acid; -   trans-4-[(2R,4R)-4-{[(7R)-2,2-difluoro-7-methyl-6,7-dihydro-2H-furo[2,3-f][1,3]benzodioxole-7-carbonyl]amino}-7-methoxy-3,4-dihydro-2H-1-benzopyran-2-yl]cyclohexane-1-carboxylic     acid; -   trans-4-[(2R,4R)-7-(difluoromethoxy)-4-{[(7R)-2,2-difluoro-7-methyl-6,7-dihydro-2H-furo[2,3-f][1,3]benzodioxole-7-carbonyl]amino}-3,4-dihydro-2H-1-benzopyran-2-yl]cyclohexane-1-carboxylic     acid; and -   trans-4-[(2R,4R)-4-{[(7R)-2,2-difluoro-7-methyl-6,7-dihydro-2H-furo[2,3-f][1,3]benzodioxole-7-carbonyl]amino}-7-(trifluoromethoxy)-3,4-dihydro-2H-1-benzopyran-2-yl]cyclohexane-1-carboxylic     acid.

In one embodiment, the additional therapeutic agent is a CFTR amplifier. CFTR amplifiers enhance the effect of known CFTR modulators, such as potentiators and correctors. Examples of CFTR amplifier include PTI130 and PTI-428. Examples of amplifiers are also disclosed in publications: WO2015138909 and WO2015138934.

In one embodiment, the additional therapeutic agent is a CFTR stabilizer. CFTR stabilizers enhance the stability of corrected CFTR that has been treated with a corrector, corrector/potentiator or other CFTR modulator combination(s). An example of a CFTR stabilizer is cavosonstat. Examples of stabilizers are also disclosed in publication: WO2012048181.

In one embodiment, the additional therapeutic agent is an agent that reduces the activity of the epithelial sodium channel blocker (ENaC) either directly by blocking the channel or indirectly by modulation of proteases that lead to an increase in ENaC activity (e.g., serine proteases, channel-activating proteases). Exemplary of such agents include camostat (a trypsin-like protease inhibitor), QAU145, 552-02, GS-9411, INO-4995, Aerolytic, amiloride, and VX-371. Additional agents that reduce the activity of the epithelial sodium channel blocker (ENaC) can be found, for example, in PCT Publication No. WO2009074575 and WO2013043720; and U.S. Pat. No. 8,999,976.

In one embodiment, the ENaC inhibitor is VX-371.

In one embodiment, the ENaC inhibitor is SPX-101 (S18).

In one embodiment, the In one embodiment, the present invention provides pharmaceutical compositions comprising a compound of the invention, or a pharmaceutically acceptable salt thereof, and one or more additional therapeutic agents. In a particular embodiment, the additional therapeutic agents are selected from the group consisting of CFTR modulators and CFTR amplifiers. In a further embodiment, the additional therapeutic agents are CFTR modulators. In one embodiment, the present invention provides pharmaceutical compositions comprising a compound of the invention, or a pharmaceutically acceptable salt thereof, one potentiator, and one or more additional correctors.

This invention also is directed to kits that comprise one or more compounds and/or salts of the invention, and, optionally, one or more additional therapeutic agents.

This invention also is directed to methods of use of the compounds, salts, compositions, and/or kits of the invention to, with or without one or more additional therapeutic agents, for example, modulate the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) protein, and treat a disease treatable by modulating the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) protein (including cystic fibrosis, Sjögren's syndrome, pancreatic insufficiency, chronic obstructive lung disease, and chronic obstructive airway disease).

Examples Chemical Synthetic Procedures General

The compounds of the invention can be better understood in connection with the following synthetic schemes and methods which illustrate a means by which the compounds may be prepared.

The compounds of this invention can be prepared by a variety of synthetic procedures. Representative procedures are shown in, but are not limited to, Schemes 1-6. In Schemes 1-6, the variables R¹, R², R³ and R⁴ are as described in the Summary.

Optimum reaction conditions and reaction times for each individual step may vary depending on the particular reactants employed and substituents present in the reactants used. Unless otherwise specified, solvents, temperatures and other reaction conditions may be readily selected by one of ordinary skill in the art. Specific procedures are provided in the Synthetic Examples section. Reactions may be further processed in the conventional manner, e.g. by eliminating the solvent from the residue and further purified according to methodologies generally known in the art such as, but not limited to, crystallization, distillation, extraction, trituration and chromatography. Unless otherwise described, the starting materials and reagents are either commercially available or may be prepared by one skilled in the art from commercially available materials using methods described in the chemical literature.

Routine experimentations, including appropriate manipulation of the reaction conditions, reagents and sequence of the synthetic route, protection of any chemical functionality that may not be compatible with the reaction conditions, and deprotection at a suitable point in the reaction sequence of the method are included in the scope of the invention. Suitable protecting groups and the methods for protecting and deprotecting different substituents using such suitable protecting groups are well known to those skilled in the art; examples of which can be found in T. Greene and P. Wuts, Protecting Groups in Organic Synthesis (3^(rd) ed.), John Wiley & Sons, NY (1999), which is incorporated herein by reference in its entirety. Synthesis of the compounds of the invention can be accomplished by methods analogous to those described in the synthetic schemes described hereinabove and in specific examples.

Starting materials, if not commercially available, can be prepared by procedures selected from standard organic chemical techniques, techniques that are analogous to the synthesis of known, structurally similar compounds, or techniques that are analogous to the above described schemes or the procedures described in the synthetic examples section.

When an optically active form of a compound is required, it can be obtained by carrying out one of the procedures described herein using an optically active starting material (prepared, for example, by asymmetric induction of a suitable reaction step), or by resolution of a mixture of the stereoisomers of the compound or intermediates using a standard procedure (such as chromatographic separation, recrystallization or enzymatic resolution).

Similarly, when a pure geometric isomer of a compound is required, it can be prepared by carrying out one of the above procedures using a pure geometric isomer as a starting material, or by resolution of a mixture of the geometric isomers of the compound or intermediates using a standard procedure such as chromatographic separation.

The compounds of the invention can be prepared from readily available starting materials using the following general methods and procedures. It will be appreciated that where typical or preferred process conditions (i.e. reaction temperatures, times, mole ratios of reactants, solvents, pressures, etc.) were given, other process conditions can also be used unless otherwise stated. Optimum reaction conditions may vary with the particular reactants or solvent used, but such conditions can be determined by one skilled in the art by routine optimization procedures.

The following methods are presented with details as to the preparation of a compound of the invention as defined hereinabove and the comparative examples. A compound of the invention may be prepared from known or commercially available starting materials and reagents by one skilled in the art of organic synthesis.

All reagents were of commercial grade and were used as received without further purification, unless otherwise stated. Commercially available anhydrous solvents were used for reactions conducted under inert atmosphere. Reagent grade solvents were used in all other cases, unless otherwise specified. Column chromatography was performed on silica gel 60 (35-70 μm). Thin layer chromatography was carried out using pre-coated silica gel F-254 plates (thickness 0.25 mm). ¹H NMR spectra were recorded on a Bruker Advance 300 NMR spectrometer (300 MHz). Chemical shifts (δ) for ¹H NMR spectra were reported in parts per million (ppm) relative to tetramethylsilane (δ 0.00) or the appropriate residual solvent peak, i.e. CHCl₃ (δ 7.27), as internal reference. Multiplicities were given as singlet (s), doublet (d), triplet (t), quartet (q), quintuplet (quin), multiplet (m) and broad (br). Electrospray MS spectra were obtained on a Waters platform LC/MS spectrometer or with Waters Acquity H-Class UPLC coupled to a Waters Mass detector 3100 spectrometer. Columns used: Waters Acquity UPLC BEH C18 1.7 μm, 2.1 mm ID×50 mm L, Waters Acquity UPLC BEH C18 1.7 μm, 2.1 mm ID×30 mm L, or Waters Xterra® MS 5 μm C18, 100×4.6 mm. The methods were using either MeCN/H₂O gradients (H₂O contains either 0.1% TFA or 0.1% NH₃) or Methanol/H₂O gradients (H₂O contains 0.05% TFA). Microwave heating was performed with a Biotage® Initiator. Electrospray MS spectra were obtained on Waters Acquity UPLC systems coupled to Waters SQD or SQD2 mass spectrometers. Columns used: Waters Acquity UPLC BEH C18 1.7 μm, 2.1 mm ID×50 mm L or Waters Acquity UPLC BEH C18 1.7 μm, 2.1 mm ID×30 mm L. The methods were using MeCN/H₂O gradients (both MeCN and H₂O contained either 0.1% formic acid or 0.05% NH₃).

For the compounds purified by preparative chromatography, an XSelect™ CSH Prep Guard Column, C18 19×10 mm 5 μm (Waters) with an XSelect™ CSH Prep OBD Column, C18 19×100 mm 5 μm (Waters) and a gradient of 0.1% formic acid in water (A) and acetonitrile (B) at a flow rate of 20 mL/minute is used. Alternatively, an XBridge™ Prep Guard Column, C18 19×10 mm 5 μm (Waters) with a XBridge™ Prep OBD Column, C18 19×100 mm 5 μm (Waters) and a gradient of 0.5% NH₃ in water (A) and acetonitrile (B) at a flow rate of 20 mL/minute is used. After elution, the solvent was removed under vacuum to provide the product. For the compounds purified by preparative chromatography, an XBridge™ Prep Guard Column, C18 19×10 mm 5 μm (Waters) with a XBridge™ Prep OBD Column, C18 30×100 mm 5 μm (Waters) and a gradient of 0.1% formic acid in water (A) and acetonitrile (B) at a flow rate of 50 mL/minute were used. Alternatively, a gradient of 0.1% DEA in water (A) and acetonitrile (B) at a flow rate of 50 mL/minute was used on the same references of guard column and column. After elution, the solvent was removed under vacuum to provide the dry product.

Alternatively, compounds were purified by automated reversed phase HPLC, using a Phenomenex® Luna® C8(2), 5 μm, 100 Å, 50×30 mm, with a SecurityGuard™ 15×30 mm guard column, and a gradient of acetonitrile (A) and 0.1% trifluoroacetic acid in water (B), at a flow rate of 40 mL/min (0-1.0 minute 10% A, 1.0-9.0 minutes linear gradient 10-100% A, 9.0-9.5 minutes 100% A, 9.5-10.0 minutes linear gradient 100-10% A). After elution, solvent was removed under vacuum to provide the pure product.

Alternatively, compounds were purified by automated reversed phase HPLC, using a C18 column, and a gradient of acetonitrile (A) and 0.1% trifluoroacetic acid in water (B), at a flow rate of 50 mL/min (0-0.5 minute 10% A, 0.5-6.0 minutes linear gradient 10-100% A, 6.0-7.0 minutes 100% A, 7.0-8.0 minutes linear gradient 100-10% A). After elution, solvent was removed under vacuum to provide the pure product.

Racemic mixtures were separated on an Agilent HP1100 system with UV detection. Column used: Chiralpak® IA (10×250 mm, 5 μm). Solvents used: iPrOH and tBME. Enantiomeric purity was determined on an Agilent HP1100 system with UV detection. Column used: Chiralpak IA (4.6×250 mm, 5 μm). Solvents used: iPrOH and tBME.

List of abbreviations used in the experimental section:

Abbreviation Definition Bn benzyl Boc tert-butoxycarbonyl Et ethyl Me methyl Ph phenyl Pr propyl Tf trifluoromethanesulfonyl OTf trifluormethanesulfonate TMS trimethylsilyl DCM dichloromethane MeCN acetonitrile DMA N,N-dimethylacetamide DMF N,N-dimethylformamide AcOH or HOAc acetic acid eq or equiv equivalents TFA trifluoroacetic acid THF tetrahydrofuran NMR nuclear magnetic resonance DMSO dimethyl sulfoxide LC/MS or LCMS liquid chromatography-mass spectrometry EtOAc ethyl acetate EtOH ethanol MeOH methanol tBuOH or t-BuOH tert-butanol tBME or MTBE tert-butyl methyl ether s singlet br s broad singlet d duplet dd double duplet m multiplet min minute h hours mL milliliter μL microliter g gram mg milligram kg kilogram RT room(ambient) temperature Et₃N or NEt₃ triethylamine DIPEA diisopropylethylamine TMEDA tetramethylethylenediamine DME 1,2-Dimethoxyethane DMAP dimethylaminopyridine EDC N-ethyl-N′-(3-dimethylaminopropyl)carbodiimide mmol millimoles HPLC high pressure liquid chromatography HOBt 1-hydroxybenzotriazole hydrate MS mass spectrum NMR nuclear magnetic resonance TLC thin layer chromatography NMP N-methylpyrrolidone ppm parts per million psi pounds per square inch Pd(OAc)₂ palladium(II) acetate Xantphos 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene SM starting material Sphos 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl Cpd compound Int intermediate MW molecular weight Mes molecular weight measured NA not active Pd(dppf)Cl₂ [1,1′- bis(diphenylphosphino)ferrocene] dichloropalladium(II) Pd(dppf)Cl₂•CH₂Cl₂ [1,1′- or bis(diphenylphosphino)ferrocene] Pd(dppf)Cl₂•DCM dichloropalladium(II) complex with dichloromethane μm micrometer iPrOH iso-propanol DBU 1,8-diazabicycloundec-7-ene DPPA diphenylphosphoryl azide LiHMDS lithium hexamethyldisilazide or lithium bis(trimethylsilyl)amide KHMDS potassium hexamethyldisilazide or potassium bis(trimethylsilyl)amide BINAP 1,1′-binaphthyl-2,2′-diamine rac-BINAP rac-1,1′-binaphthyl-2,2′-diamine TfOH trifluoromethanesulfonic acid Tf₂O trifluoromethanesulfonic anhydride XPhos 2-dicyclohexylphosphino-2′,4′,6′- triisopropylbiphenyl XPhos Pd G1 (2-dicyclohexylphosphino-2′,4′,6′-triisopropyl-1, 1′-biphenyl)[2-(2-aminoethyl)phenyl)]palladium (II) chloride K₂CO₃ potassium carbonate MgSO₄ magnesium sulfate NaHCO₃ sodium hydrogencarbonate Na₂CO₃ sodium bicarbonate Na₂SO₄ sodium sulfate CO carbon monoxide NaCl sodium chloride NaH sodium hydride LiOH lithium hydroxide

Synthetic Preparation of the Compounds of the Invention

General Synthetic Routes

The compounds of the invention and the comparative examples can be produced according to the following schemes.

Method A: Synthesis of Benzyl Esters

To a solution of the carboxylic acid (1.0 equiv) in either dry DMF or dry acetonitrile is added K₂CO₃ (1.3 equiv) followed by benzylbromide (1.1 equiv). The reaction mixture is heated at a temperature ranging from RT to 85° C. from 2 h to 4 days, and then partitioned between brine and either ethyl acetate or dichloromethane. The organic layer is separated, washed with brine and saturated ammonium chloride, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue is purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate) to afford the titled compound.

Illustrative Synthesis of Intermediate BE01: 1-Methyl-Cyclobutanecarboxylic Acid Benzyl Ester

To a solution of 1-methylcyclobutanecarboxylic acid (CAS:32936-76-8, 0.5 g, 4.38 mmol, 1.0 equiv) in dry DMF was added K₂CO₃ (0.787 g, 5.69 mmol, 1.3 equiv) followed by benzylbromide (CAS: 100-39-0, 0.57 mL, 4.82 mmol, 1.1 equiv). The reaction mixture was stirred at RT for 2.5 h and then diluted with ethyl acetate and brine. The organic layer was separated, washed with a saturated solution of ammonium chloride and brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue was purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate gradient from 100/0 to 90/10) to afford the titled compound.

TABLE I List of benzyl esters Int. Structure Name SM method MW BE01

1-Methyl- cyclobutanecarboxylic acid benzyl ester 32936-76- 8 A, Specific example 204 BE02

3-Methoxy- cyclobutanecarboxylic acid benzyl ester 552849- 35-1 A 220 BE03

3-Fluoro- cyclobutanecarboxylic acid benzyl ester 122665- 96-7 A 208 BE04

3-Methyl- cyclobutanecarboxylic acid benzyl ester 87863-09- 0 A 204 BE05

Benzyl 3- methyloxetane-3- carboxylate 28562-68- 7 A 206

Method B: Cyanoketone Formation

A flame-dried round bottom flask is cooled down to RT under nitrogen. A solution of 1 M LiHMDS in THF (1.5 equiv) is introduced into the flask, and then it is cooled down to −78° C. (acetone/dry ice bath). Dry MeCN (from 1.5 to 1.7 equiv) is then added dropwise under nitrogen, and the reaction mixture is stirred for 30 min at −78° C. At this point a solution of ester (1.0 equiv) in dry THF is added dropwise, and then the reaction mixture is stirred at −78° C. for 1-2 h. The reaction mixture is quenched with cold H₂O, partitioned between ethyl acetate (or diethyl ether) and H₂O. The organic layer is separated, and the aqueous layer is extracted with ethyl acetate (or diethyl ether). The aqueous fraction is then acidified to pH=1-3 with 2 N HCl and extracted with ethyl acetate (or diethyl ether or DCM). The combined organic layers are then washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the titled compound which is used as such or purified by flash chromatography on silica gel.

Illustrative Synthesis of CK01: Cyclobutyl-3-Oxo-Propionitrile

A 1 L 4 neck round bottom flask was equipped with 2 dropping funnels and a septum on top of the apparatus. The whole system was flame-dried (heat gun) for 10 minutes under vacuum and then cooled down to RT under a positive stream of nitrogen (balloon). A low-temperature thermometer was adapted under a positive stream of nitrogen, then a 1 N LiHMDS solution in THF (468.0 mL, 468.0 mmol, 1.5 equiv) was cannulated into the flask using a positive stream of nitrogen. The solution was cooled down to −78° C. (dry ice/acetone cooling bath) as confirmed with the thermometer. Dry MeCN (24.4 mL, 468.0 mmol, 1.5 equiv) was added via syringe into the first dropping funnel, and then added dropwise (over 20 min) into the reaction mixture. After the end of the addition, the mixture was stirred at −78° C. for 1 h. At this point, cyclobutanecarboxylic acid ethyl ester (CAS:14924-53-9, 43.1 mL, 312.1 mmol, 1.0 equiv) as a solution in dry THF (106 mL) was introduced into the second dropping funnel. This solution was slowly added over 2 h into the reaction mixture at −78° C. The mixture was stirred at −78° C. for 2 h. The reaction mixture was poured into 300 mL of cold water, stirred for 30 min and allowed to warm to RT. The mixture was then partitioned between ethyl acetate and H₂O. The organic layer was separated, and the aqueous layer was extracted with ethyl acetate (3×300 mL). The combined organic phases were discarded. The aqueous layer was then acidified with 100 mL of 2 N HCl, then extracted with ethyl acetate (3×300 mL), washed with 50 mL of brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the titled compound which was used without further purification.

TABLE II List of cyanoketones Int. Structure Name SM method MW Mes 29509- 06-6

4-Methyl-3-oxo- pentanenitrile 111 CK01, 118431- 89-3

3-Cyclobutyl-3- oxo-propionitrile 14924- 53-9 B, Specific example 123 59997- 51-2

4,4-Dimethyl-3- oxo-pentanenitrile 125 887594- 13-0

3-(2-Cyano- acetyl)-azetidine- 1-carboxylic acid tert-butyl ester 224 118431- 88-2

3-Cyclopropyl-3- oxo-propionitrile 109 CK02

3-(1-Methyl- cyclobutyl)-3- oxo-propionitrile BE01 B 137 138 CK03

3-(cis-3-Methoxy- cyclobutyl)-3- oxo-propionitrile BE02 B 153 29509- 06-6

4-Methyl-3-oxo- pentanenitrile 111 1234616- 26-2

3-(3,3-Difluoro- cyclobutyl)-3- oxo-propionitrile 159 CK04

3-(3,3-Dimethyl- cyclobutyl)-3- oxo-propionitrile 3854- 83-9 B 151 CK05

3-(3-Fluoro- cyclobutyl)-3- oxo-propionitrile BE03 B 141.15 CK06

3-(trans-3- Methyl- cyclobutyl)-3- oxo-propionitrile BE04 B 137.18 CK07

3-Oxo-3- tetrahydrofuran-2- yl-propanenitrile 37443- 42-3 B 139 CK08

3-(3- Methyloxetan-3- yl)-3-oxo- propanenitrile BE05 B 139

Method C: Hydrazine Formation

Method C1: Reductive Amination

To a Solution of Ketone (1 Equiv) and Tert-Butyl Carbazate (CAS: 870-46-2, 1.0 Equiv) in anhydrous dichloromethane at 0° C. is added acetic acid (2.0 equiv) and sodium triacetoxyborohydride (CAS: 56553-60-7, 3.0 equiv). The reaction mixture is warmed up to RT and stirred for 1 h to several days (up to 8). The reaction mixture is then basified with a solution of 2 M sodium hydroxide and a saturated solution of sodium hydrogencarbonate. The two phases are separated, and the aqueous phase is extracted with dichloromethane. The combined organic phases are washed with a saturated solution of sodium hydrogencarbonate and brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the tert-butoxy carbonyl hydrazine which is used as such or purified by flash chromatography on silica gel.

Method C2: Reductive Amination

To the ketone (1 equiv) in anhydrous methanol at RT is added tert-butyl carbazate (CAS: 870-46-2, 1.0 equiv). The reaction mixture is stirred for 20 minutes at RT, then acetic acid (3.0 equiv) and sodium cyanoborohydride (CAS: 25895-60-7, 1.5 equiv) are added. The reaction mixture is stirred at RT for 1 h to several days (up to 8). The reaction mixture is then basified with a solution of 2 M sodium hydroxide and a saturated solution of sodium hydrogencarbonate. The two phases are separated, and the aqueous phase is extracted with dichloromethane. The combined organic phases are washed with a saturated solution of sodium hydrogencarbonate and brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the tert-butoxy carbonyl hydrazine which is used as such or purified by flash chromatography on silica gel.

Method C3: Tert-Butoxy Carbonyl-Deprotection

To a solution of a tert-butoxy carbonyl hydrazine intermediate from Methods C1 or C2 in anhydrous dichloromethane at RT is added 4 M HCl in dioxane (20 equiv). The reaction mixture is stirred at RT until the reaction is finished. The solids are collected by filtration, washed twice with diethyl ether, and dried in vacuo to afford the hydrazine which is used as such.

Method C4: Tert-Butoxy Carbonyl-Deprotection

A tert-butoxy carbonyl hydrazine intermediate from Methods C1 or C2 is stirred at RT in a 1:1 mixture of dichloromethane and trifluoroacetic acid until the reaction is finished. The reaction mixture is concentrated in vacuo. The residue is taken up three times with toluene and concentrated in vacuo to afford the hydrazine which is used as such.

Illustrative Synthesis of H01: (Tetrahydro-Pyran-3-Yl)-Hydrazine Di-Hydrochloride Salt

Step 1: tert-butyl N-(tetrahydropyran-3-ylamino)carbamate

To a solution of dihydro-2H-pyran-3(4H)-one (CAS: 23462-75-1, 0.6 g, 5.99 mmol, 1.0 equiv) and tert-butyl carbazate (CAS: 870-46-2, 0.792 g, 5.99 mmol, 1.0 equiv) in anhydrous dichloromethane (20 mL) at 0° C. was added acetic acid (0.685 mL, 11.98 mmol, 2.0 equiv) and sodium triacetoxyborohydride (CAS: 56553-60-7, 3.81 g, 17.97 mmol, 3.0 equiv). The reaction mixture was warmed up to RT and stirred for 24 h. The reaction mixture was then basified with a solution of 2 M sodium hydroxide (45 mL) and a saturated solution of sodium hydrogencarbonate (30 mL). The two phases were separated, and the aqueous phase was extracted with dichloromethane. The combined organic phases were washed with a saturated solution of sodium hydrogencarbonate and brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue was purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate 70/30) to afford tert-butyl 2-(oxan-3-yl)hydrazine-1-carboxylate.

Step 2: (Tetrahydro-pyran-3-yl)-hydrazine di-hydrochloride salt

To a solution of tert-butyl 2-(oxan-3-yl)hydrazine-1-carboxylate from Step 1 (0.534 g, 2.46 mmol, 1 equiv) in anhydrous dichloromethane (1.74 mL) at RT was added 4 M HCl in dioxane (12.34 mL, 49.38 mmol, 20 equiv). The reaction mixture was stirred at RT overnight, and then the solid was collected by filtration. The solid was washed twice with diethyl ether and dried in vacuo to afford the titled compound, H01.

Illustrative synthesis of H02: 4,4-Difluoro-cyclohexyl)-hydrazine bis(trifluoroacetate)

Step 1: tert-butyl N-[(4,4-difluorocyclohexyl)amino]carbamate

To 4,4-difluorocyclohexanone (CAS: 22515-18-0, 0.4 g, 2.98 mmol, 1.0 equiv) in anhydrous methanol (8.5 mL) at RT was added tert-butyl carbazate (CAS: 870-46-2, 0.394 g, 2.98 mmol, 1.0 equiv). The reaction mixture was stirred for 20 minutes at RT, and then acetic acid (0.51 mL, 8.95 mmol, 3.0 equiv) and sodium cyanoborohydride (CAS: 25895-60-7, 0.281 g, 4.47 mmol, 1.5 equiv) were added. The reaction mixture was stirred at RT overnight. The reaction mixture was then basified with a solution of 2 M sodium hydroxide (22 mL) and a saturated solution of sodium hydrogencarbonate (15 mL). The two phases were separated, and the aqueous phase was extracted with dichloromethane. The combined organic phases were washed with a saturated solution of sodium hydrogencarbonate and brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue was purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate gradient from 100/0 to 50/50) to afford tert-butyl 2-(4,4-difluorocyclohexyl)hydrazine-1-carboxylate.

Step 2: 4,4-Difluoro-cyclohexyl)-hydrazine bis(trifluoroacetate)

The tert-butyl 2-(4,4-difluorocyclohexyl)hydrazine-1-carboxylate intermediate from Step 1 (0.2 g, 0.8 mmol, 1 equiv) was stirred at RT in a 1:1 mixture of dichloromethane (0.65 mL) and trifluoroacetic acid (0.65 mL) for 1.5 h. The reaction mixture was concentrated in vacuo. The residue was taken up three times with toluene and concentrated in vacuo to afford the titled compound, H02.

Synthesis of H04: (2, 4-Dimethoxy-benzyl)-hydrazine di-hydrochloride salt

Step 1: tert-butyl N-[(E)-(2,4-dimethoxyphenyl)methyleneamino]carbamate

To 2,4-dimethoxybenzaldehyde (CAS: 613-45-6, 37.82 g, 228 mmol, 1.0 equiv) in methanol at RT was added tert-butyl carbazate (CAS: 870-46-2, 30.08 g, 228 mmol, 1.0 equiv) and MgSO₄ (18.9 g). The reaction mixture was stirred at RT overnight. The reaction mixture was filtered through a pad of diatomaceous earth. The solids were washed with dichloromethane, and the filtrate was concentrated in vacuo. The residue was taken up in diethyl ether (120 mL) and stirred at RT. The resulting slurry was filtered. The solid was washed three times with diethyl ether and dried in vacuo to afford tert-butyl 2-[(2,4-dimethoxyphenyl)methylidene]hydrazine-1-carboxylate.

Step 2: tert-butyl N-[(E)-(2,4-dimethoxyphenyl)methylamino]carbamate

A 2-L round bottom flask under nitrogen atmosphere was charged with methanol (1.3 L), 10% palladium on carbon (13.6 g), and tert-butyl 2-[(2,4-dimethoxyphenyl)methylidene]hydrazine-1-carboxylate from Step 1 (68.41 g, 228 mmol, 1 equiv). The reaction mixture was placed under vacuum then filled with hydrogen and kept under a hydrogen atmosphere (balloon). The reaction mixture was stirred at RT for 5 h. The reaction mixture was filtered through a pad of diatomaceous earth. The solids were washed with methanol, and the filtrate was concentrated in vacuo. The resulting residue was purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate, gradient from 50/50 to 40/60) to afford tert-butyl 2-[(2,4-dimethoxyphenyl)methyl]hydrazine-1-carboxylate.

Step 3: (2,4-Dimethoxy-benzyl)-hydrazine di-hydrochloride salt

A 2-L round bottom flask was charged with tert-butyl 2-[(2,4-dimethoxyphenyl)methyl]hydrazine-1-carboxylate from Step 2 (59.8 g, 211 mmol, 1.0 equiv), then a solution of 4 M HCl in dioxane (600 mL, 2400 mmol, 11.35 equiv) was added. The reaction mixture was stirred at RT overnight. The reaction mixture was filtered. The solid was washed three times with diethyl ether and dried in vacuo to afford the titled compound, H04.

Synthesis of H05: 4-(3-hydrazinylphenyl)morpholine

A solution of sodium nitrite (221 mg, 3.2 mmol) in water (1.5 mL) was added dropwise at −5° C. to a solution of 3-morpholin-4-ylaniline (CAS: 159724-40-0, 475 mg, 2.7 mmol). The reaction mixture was stirred for 1 hour, and a solution of tin (II) chloride dihydrate in concentrated HCl (3 mL) was added dropwise. The reaction mixture was allowed to warm to RT for 1 hour. The precipitate was filtered, washed with petroleum ether and partitioned between water and ethyl acetate. The aqueous phase was basified to pH 9-10 and extracted three times with ethyl acetate. The combined aqueous layer was evaporated under reduced pressure. The titled compound was used as such without further purification.

TABLE III List of Hydrazines Int. Structure Name SM method MW Mes H01

(Tetrahydro-pyran- 3-yl)-hydrazine di-hydrochloride salt 23462- 75-1 C1, C3 Specific example 116 H02

(4,4-Difluoro- cyclohexyl)- hydrazine di-trifluoroacetic acid salt 22515- 18-0 C2, C4 Specific example 150 H03

(Tetrahydro-furan- 3-yl)-hydrazine di-hydrochloride salt 22929- 52-8 C2, C3 102 H04

(2,4-Dimethoxy- benzyl)-hydrazine di-hydrochloride salt 613- 45-6 Specific example 182 183 H05

4-(3- Hydrazinylphenyl) morpholine 15972 4-40-0 Specific example 193 194 H06

(3- Benzyloxycyclohexyl) hydrazine 12399 0-98- 7 C2, C3 220 221 H07

Benzyl 4- hydrazinopiperidine- 1-carboxylate 19099- 93-5 C2, C3 249 250 H08

Benzyl 3- hydrazinopyrrolidine- 1-carboxylate 13031 2-02-6 C2, C3 235 236 H09

Benzyl 3- hydrazinopiperidine- 1-carboxylate 61995- 20-8 C2, C4 249 250

Method D: Aryl Hydrazones Formation

An aryl bromide (1.05 equiv), benzophenone hydrazone (CAS: 5350-57-2, 1.0 equiv) and rac-BINAP (CAS: 98327-87-8, 0.06 equiv) are introduced in a round bottom flask at RT and suspended in anhydrous toluene. The slurry is purged with argon (bubbling). Then palladium(II) acetate (CAS: 3375-31-3, 0.02 equiv) and sodium tert-butoxide (CAS: 865-48-5, 1.3 equiv) are added, and the resulting slurry is purged with argon again. The reaction mixture is heated at 100° C. until the reaction is finished. The reaction mixture is cooled down to RT and filtered through a pad of diatomaceous earth. Solids were washed with ethyl acetate, and the filtrate is concentrated in vacuo. The titled compound is obtained from the crude filtrate either by precipitation from a suitable solvent or by purification by flash chromatography on silica gel (eluent system: heptane/ethyl acetate).

Illustrative synthesis of ArH01: [3-(N′-Benzhydrylidene-hydrazino)-phenyl]-dimethyl-amine

3-Bromo-N,N-dimethylaniline (CAS:16518-62-0, 18.55 mL, 130 mmol, 1.05 equiv), benzophenone hydrazone (CAS: 5350-57-2, 24.29 g, 124 mmol, 1.0 equiv) and rac-BINAP (CAS: 98327-87-8, 4.62 g, 7.43 mmol, 0.06 equiv) were combined in a round bottom flask at RT and suspended in anhydrous toluene (80 mL). The slurry was purged with argon (bubbling), and then palladium(II) acetate (CAS: 3375-31-3, 0.556 g, 2.48 mmol, 0.02 equiv) and sodium tert-butoxide (CAS: 865-48-5, 15.46 g, 161 mmol, 1.3 equiv) were added. The resulting slurry was purged with argon again, and the reaction mixture was heated at 100° C. for 1.5 h. The reaction mixture was cooled down to RT and filtered through a pad of diatomaceous earth. The solids were washed with ethyl acetate, and the filtrate was concentrated in vacuo. The residue was taken up in diethyl ether, and stirred at RT. The resulting slurry was filtered. The collected solid was washed twice with diethyl ether and dried in vacuo to afford the titled compound.

TABLE IV List of Arylhydrazones Int. Structure Name SM method MW Mes ArH01

[3-(N- Benzhydrylidene- hydrazino)-phenyl]- dimethyl-amine 16518- 62-0 D 315 316 ArH02

N-Benzhydrylidene-N′- (3-morpholin-4-yl- phenyl)-hydrazine 197846- 82-5 D 357 358 ArH03

N-Benzhydrylidene-N′- (3-fluoro-5-methoxy- phenyl)-hydrazine 29578- 39-0 D 320 321 ArH04

N-Benzhydrylidene-N′- (6-fluoro-pyridin-2-yl)- hydrazine 144100- 07-2 D 291 292 ArH05

N-Benzhydrylidene-N′- (2-chloro-pyridin-4-yl)- hydrazine 73583- 37-6 D 308 309 ArH06

N- (benzhydrylideneamino)- 5-morpholino- pyridin-3-amine 200064- 13-7 D 358 359 ArH07

N- (benzhydrylideneamino)- 4-chloro-pyridin-2- amine 22918- 01-0 D 307 308

Methods E1-E7: Synthesis of Aminopyrazoles Method E1: Cyclization of Hydrazines with 3-Aminocrotononitrile

3-Aminocrotononitrile (CAS: 1118-61-2, 1.1 equiv), the hydrazine hydrochloride (1.0 equiv) and few drops of 1 N HCl solution are heated in EtOH at reflux until the reaction is finished. The reaction mixture is cooled down to RT and then is diluted with a saturated solution of sodium hydrogencarbonate. The aqueous phase is extracted with dichloromethane. The combined organic phases are filtered through a phase separator and concentrated under vacuum to afford the aminopyrazole which is used as such.

Illustrative synthesis of AMP01: 5-Methyl-2-(3-trifluoromethoxy-phenyl)-2H-pyrazol-3-ylamine

3-Aminocrotononitrile (CAS: 1118-61-2, 0.5 g, 6.09 mmol, 1.1 eq;), 3-(trifluoromethoxy)phenylhydrazine hydrochloride (1.27 g, 5.54 mmol, 1.0 equiv) and two drops of 1 N HCl solution were heated in EtOH (1.5 mL) at reflux overnight. The reaction mixture was diluted with a saturated solution of sodium hydrogencarbonate, and the aqueous phase was extracted with dichloromethane. The combined organic phases were filtered through a phase separator and concentrated under vacuum to afford the titled compound which was used as such.

Method E2: Cyclization of Hydrochloride Salts of Hydrazines with Cyano Ketones

A round bottom flask is charged with the cyanoketone (from 1.0 to 1.5 equiv), the hydrazine hydrochloride or dihydrochloride (1 equiv) and EtOH. This mixture is stirred at a temperature ranging from RT to refluxing ethanol until the reaction is finished. Then the reaction mixture is concentrated in vacuo to afford a crude mixture which is used as such or undergoes one of the following processes:

Either the crude mixture is taken up in a suitable solvent. The resulting slurry is filtered, and the solids are washed with the same solvent and dried in vacuo to afford the aminopyrazole as its hydrochloride salt which is used as such or is taken up in either ethyl acetate or dichloromethane and basified with a saturated solution of either potassium carbonate or sodium hydrogencarbonate. The two phases are separated, and the aqueous phase is extracted with either ethyl acetate or dichloromethane. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the aminopyrazole as its free base which is used as such or further purified by flash chromatography on silica gel.

Or alternatively this crude mixture is partitioned between water and either ethyl acetate or dichloromethane. The two phases are separated, and the aqueous phase is washed with either ethyl acetate or dichloromethane, basified with a saturated solution of sodium hydrogencarbonate and extracted with either ethyl acetate or dichloromethane. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the aminopyrazole as its free base which is used as such or further purified by flash chromatography on silica gel.

Or alternatively the crude mixture is partitioned between a saturated aqueous solution of NaHCO₃ and dichloromethane. The organic phase is separated using a phase separator and concentrated in vacuo to afford the titled compound as its free base which is used as such or further purified by flash chromatography on silica gel.

Illustrative synthesis of AMP29: 5-Cyclobutyl-2-phenyl-2H-pyrazol-3-ylamine

A round bottom flask was charged with 3-cyclobutyl-3-oxo-propionitrile CK01 (19.6 g, 159 mmol, 1.1 equiv), phenylhydrazine hydrochloride (CAS: 59-88-1, 20.92 g, 145 mmol, 1.0 equiv) and EtOH (210 mL). The reaction mixture was stirred at reflux for 1 h. Then the reaction mixture was concentrated in vacuo to afford a crude mixture which was taken up in diethyl ether. The resulting slurry was filtered, and the solid was washed with diethyl ether and dried in vacuo to afford the titled compound as its hydrochloride salt which was taken up in dichloromethane and basified with a saturated solution of sodium hydrogencarbonate. The two phases were separated, and the aqueous phase was extracted with dichloromethane. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the titled compound as its free base.

Illustrative synthesis of AMP35: 5-cyclobutyl-2-cyclohexyl-2H-pyrazol-3-ylamine

A round bottom flask was charged with 3-cyclobutyl-3-oxo-propionitrile ([118431-89-3], 20.4 g, 166 mmol), cyclohexylhydrazine hydrochloride ([24214-73-1], 25 g, 166 mmol) and EtOH (200 mL). The reaction mixture was refluxed overnight and cooled down to RT. Next, the mixture was concentrated and water (150 mL) was added. The pH was modified till pH=7 with a saturated aqueous K₂CO₃ solution. Subsequently, the aqueous phase was extracted with DCM. The obtained organic phase was dried and concentrated to give a yellow solid. Trituration with MTBE gave the titled compound.

Illustrative synthesis of AMP93: 3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazol-5-amine

A round bottom flask was charged with 3-cyclobutyl-3-oxo-propionitrile (CK01, 10 g, 81.4 mmol), 4-fluorophenylhydrazine hydrochloride ([823-85-8], 12 g, 74 mmol) and EtOH (35 mL). The reaction mixture was refluxed for 2 hours and cooled down to RT. Half of the solvent was removed in vacuo. The mixture was vigorously stirred and diisopropyl ether (350 mL) was added. The stirring was continued for 1 hour, and the formed precipitate was filtered, washed with diisopropyl ether and dried at 40° C. under reduced pressure to give the titled compound.

Illustrative synthesis of AMP94: 1-tert-butyl-3-cyclobutyl-1H-pyrazol-5-amine

A round bottom flask was charged with 3-cyclobutyl-3-oxo-propionitrile (CK01, 12.3 g, 0.1 mol), tert-butylhydrazine hydrochloride ([7400-27-3], 13.5 g, 0.11 mol) and EtOH (150 mL). The reaction mixture was refluxed for 20 hours and cooled down to RT. Half of the solvent was removed by concentration in vacuo, and the mixture was cooled in an ice bath. The formed precipitate was collected by filtration and washed successively with diethyl ether and n-pentane. The filtrate was allowed to stand for 1 hour, and the formed precipitate was again collected by filtration and washed with diethyl ether and n-pentane. The combined solids were stirred in ethyl acetate and a saturated solution of NaHCO₃. The organic phase was dried over sodium sulfate, filtered and evaporated under reduced pressure to give the titled compound.

Method E3: Cyclization of Cyano Ketones with Hydrazines Either as Free Base, Hydrochloride or TFA Salt, in the Presence of an Organic Base

To the hydrazine either as free base or as a hydrochloride or a trifluoroacetic acid mono or di-salt (1 equiv) and the cyanoketone (from 1.0 to 1.5 equiv) in ethanol or toluene at RT is added DIPEA (from 0 to 2.0 equiv). Then the reaction mixture is heated at reflux until the reaction is finished. The reaction mixture is concentrated in vacuo to afford a crude mixture which is used as such or purified by flash chromatography on silica gel to afford the aminopyrazole as its free base.

Illustrative synthesis of AMP26: 2-Cyclopentyl-5-isopropyl-2H-pyrazol-3-ylamine

To cyclopentylhydrazine hydrochloride (CAS: 24214-72-0, 0.35 g, 2.56 mmol, 1.0 equiv) and 4-methyl-3-oxo-pentanenitrile (CAS: 29509-06-6, 0.33 mL, 2.82 mmol, 1.1 equiv) in toluene (12.8 mL) at RT was added DIPEA (0.82 mL, 5.12 mmol, 2.0 equiv). Then the reaction mixture was heated at reflux for 1.5 h. The reaction mixture was cooled down to RT and concentrated in vacuo to afford a crude mixture which was purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate gradient from 100/0 to 30/70) to afford the titled compound.

Method E4: Cyclization of Arylhydrazones with Cyanoketones

To the arylhydrazone (1 equiv) and the cyanoketone (from 1.0 to 2 equiv) in ethanol at RT is added an aqueous solution of 2 M HCl or 12 M HCl (5 equiv). Then the reaction mixture is heated at reflux until the reaction is finished. Then the reaction mixture is cooled down to RT and undergoes one of the following processes.

The reaction mixture is concentrated to dryness in vacuo to afford a crude mixture. The aminopyrazole is obtained from this crude mixture by precipitation from a suitable solvent to afford the aminopyrazole as its hydrochloride salt and used as such.

Ethanol from the reaction mixture is removed in vacuo. The resulting aqueous residue is diluted with an aqueous solution of 2 M HCl, washed with dichloromethane, then basified with a saturated solution of sodium hydrogencarbonate and extracted with dichloromethane. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the aminopyrazole as a free base which is used as such or further purified by flash chromatography on silica gel.

Illustrative synthesis of AMP06: 2-(3-Dimethylamino-phenyl)-5-isopropyl-2H-pyrazol-3-ylamine

To [3-(N-benzhydrylidene-hydrazino)-phenyl]-dimethyl-amine (ArH01, 25.57 g, 81 mmol, 1 equiv) and 4-methyl-3-oxo-pentanenitrile (CAS: 29509-06-6, 10.57 mL, 89.2 mmol, 1.1 equiv) in ethanol (255 mL) at RT was added an aqueous solution of 2 M HCl (203 mL, 405 mmol, 5 equiv). Then the reaction mixture was heated at reflux overnight. The reaction mixture was cooled down to RT, and ethanol from the reaction mixture was removed in vacuo. The resulting aqueous residue was diluted with an aqueous solution of 2 M HCl, washed with dichloromethane, then basified with a saturated solution of sodium hydrogencarbonate and extracted twice with dichloromethane. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the titled compound which was used as such.

Method E5: SNAr on 2-(2-chloro-pyridin-4-yl)-yl-2H-pyrazol-3-ylamine intermediates

A sealed tube is charged with the 2-(2-chloro-pyridin-4-yl)-yl-2H-pyrazol-3-ylamine intermediate (1 equiv), the amine (from 10 to 15 equiv), DIPEA (3 equiv) and DMA. This mixture is heated at a temperature ranging from 130° C. to 160° C. until the reaction is finished. Then the reaction mixture is cooled down to RT and partitioned between ethyl acetate and water. The two phases are separated and the aqueous phase is extracted with ethyl acetate. The combined organic phases are washed with water and brine, dried over MgSO₄, filtered and concentrated in vacuo. The substituted aminopyrazole is obtained from the crude mixture either by precipitation or by purification by flash chromatography on silica gel.

Illustrative synthesis of AMP22: 5-Isopropyl-2-(2-pyrrolidin-1-yl-pyridin-4-yl)-2H-pyrazol-3-ylamine

A sealed tube was charged with 2-(2-chloro-pyridin-4-yl)-yl-2H-pyrazol-3-ylamine intermediate (AMP20, 1.2 g, 5.07 mmol, 1 equiv), pyrrolidine (CAS: 123-75-1, 4 mL, 50.7 mmol, 10 equiv), DIPEA (2.6 mL, 15.2 mmol, 3 equiv) and DMA (10 mL). This mixture was heated at 130° C. for 2 h. Then the reaction mixture was cooled down to RT, and additional pyrrolidine (CAS: 123-75-1, 1 mL, 12.67 mmol, 2.5 equiv) was introduced, and the reaction mixture was heated at 130° C. for 30 minutes. Then the reaction mixture was cooled down to RT and partitioned between ethyl acetate and water. The two phases were separated, and the aqueous phase was extracted twice with ethyl acetate. The combined organic phases were washed with water (three times) and brine, dried over MgSO₄, filtered and concentrated in vacuo. The crude mixture was purified by flash chromatography on silica gel (eluent system: dichloromethane/methanol gradient from 100/0 to 97/3) to afford the titled compound.

Method E6: Buchwald Coupling

To the 2-(3-bromo-phenyl)-2H-pyrazol-3-ylamine hydrochloride salt intermediate (1 equiv) in anhydrous THF at RT under a nitrogen atmosphere is added the amine (1.2 equiv), a solution of 1 N LiHMDS in THF (5 equiv) and XPhos Pd G1 (CAS 1028206-56-5, 0.1 equiv). The reaction mixture is stirred at RT until the reaction is finished. The reaction mixture is hydrolyzed with a saturated solution of ammonium chloride and diluted with dichloromethane. The two phases are separated, and the aqueous phase is extracted with dichloromethane. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The substituted aminopyrazole is obtained from the crude mixture by purification with flash chromatography on silica gel (eluent system: heptane/ethyl acetate).

Illustrative synthesis of AMP11: 5-Isopropyl-2-(3-pyrrolidin-1-yl-phenyl)-2H-pyrazol-3-ylamine

To 2-(3-bromo-phenyl)-5-isopropyl-2H-pyrazol-3-ylamine hydrochloride salt (AMP05, 0.5 g, 1.58 mmol, 1 equiv) in anhydrous THF (5 mL) at RT under nitrogen atmosphere was added pyrrolidine (CAS: 123-75-1, 0.16 mL, 1.9 mmol, 1.2 equiv), a solution of 1 N LiHMDS in THF (8 mL, 8 mmol, 5 equiv) and XPhos Pd G1 (CAS 1028206-56-5, 0.117 g, 0.16 mmol, 0.1 equiv). The reaction mixture was stirred at RT for 5 h. The reaction mixture was treated with a saturated solution of ammonium chloride and diluted with dichloromethane. The two phases were separated, and the aqueous phase was extracted with dichloromethane. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The crude mixture was purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate gradient from 100/0 to 65/35) to afford the titled compound.

Method E7: O-Alkylation of 5-aminopyrazol-3-ol Analogues

A suspension of 5-aminopyrazol-3-ol derivative (1 equiv), cesium carbonate (1.2 equiv) and 2-bromopropane (1 equiv) in N-methylpyrrolidine is stirred at RT for 20 to 72 hours. The reaction mixture is diluted with DCM and washed with water. The organic phase is dried over sodium sulfate, filtered and concentrated under reduced pressure. The O-alkylated product is purified by flash column chromatography on silica gel.

Illustrative synthesis of AMP96: 1-(4-fluorophenyl)-3-[(propan-2-yl)oxy]-1H-pyrazol-5-amine

A suspension of 5-amino-1-(4-fluorophenyl)-1H-pyrazol-3-ol ([1247169-18-1], 800 mg, 4.14 mmol), cesium carbonate (2.15 g, 4.97 mmol) and 2-bromopropane (516 μL, 4.14 mmol) in N-methylpyrrolidine (8 mL) was stirred at RT for 20 hours. The reaction mixture was diluted with DCM and washed with water. The organic phase was dried over sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by flash column chromatography on silica gel eluting with ethyl acetate/n-heptane to yield the titled compound.

Synthesis of intermediates: AMP18 [6-(5-Amino-3-isopropyl-pyrazol-1-yl)-pyridin-2-yl]-dimethyl-amine and AMP19 5-Isopropyl-2-(6-morpholin-4-yl-pyridin-2-yl)-2H-pyrazol-3-ylamine

A sealed tube was charged with 2-(6-fluoro-pyridin-2-yl)-5-isopropyl-2H-pyrazol-3-ylamine (AMP17, 0.2 g, 0.91 mmol, 1 equiv), morpholine (CAS: 110-91-8, 0.12 mL, 1.37 mmol, 1.5 equiv), DIPEA (0.19 mL, 1.09 mmol, 1.2 equiv) and DMF (2 mL). This mixture was heated at 100° C. overnight. Then the reaction mixture was cooled down to RT and partitioned between ethyl acetate and water. The two phases were separated, and the aqueous phase was extracted with ethyl acetate. The combined organic phases were washed with water (three times) and brine, dried over MgSO₄, filtered and concentrated in vacuo. The crude mixture was purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate gradient from 100/0 to 60/40) to afford the two titled compounds.

Synthesis of AMP51B: ethyl 5-(tert-butoxycarbonylamino)-1-phenyl-pyrazole-3-carboxylate

Di-tert-butyl dicarbonate (613 mg, 2.8 mmol) and DMAP (686 mg, 5.6 mmol) were added at RT to a stirring solution of ethyl 5-amino-1-phenyl-1H-pyrazole-3-carboxylate (CAS: 866837-96-9, 500 mg, 2.2 mmol) in DCM (11 mL). The reaction mixture was stirred for 20 hours and diluted with DCM. The organic phase was washed with a saturated aqueous solution of NaHCO₃, separated using a phase separator, and concentrated under reduced pressure. The crude sample was purified by flash column chromatography using a gradient of petroleum ether/ethyl acetate to give the titled compound.

Synthesis of AMP53: (5-amino-1-phenyl-pyrazol-3-yl)methanol

A solution of ethyl 5-amino-1-phenyl-1H-pyrazole-3-carboxylate (CAS: 866837-96-9, 300 mg, 1.3 mmol) in THF (6.5 mL), under nitrogen atmosphere was cooled down to −78° C. Diisobutylaluminum hydride (1 M in toluene, 2.9 mL, 2.9 mmol) was added dropwise to the solution, and the stirring at −78° C. was continued for 1 hour. Methanol was added, and the reaction mixture was stirred for 30 minutes warming to RT. DCM was added, and the organic phase was washed with water. The organic phase was separated using a phase separator and concentrated under reduced pressure. The titled compound was used as such without any further purification.

Synthesis of AMP66: 2-(5-amino-1-phenyl-pyrazol-3-yl)propan-2-ol

Step 1: tert-butyl N-[5-(1-hydroxy-1-methyl-ethyl)-2-phenyl-pyrazol-3-yl]carbamate

A solution of AMP51B (100 mg, 0.3 mmol) in THF (1.5 mL), under nitrogen atmosphere was cooled down in an ice bath. Methylmagnesium iodide (3 M in diethyl ether, 0.2 mL, 0.6 mmol) was added dropwise to the solution, and the stirring at 0° C. was continued for 20 minutes. The reaction mixture was allowed to warm to RT for 2.5 hours. LCMS analysis only showed little conversion. The reaction mixture was cooled in an ice bath and 2 equivalents of methylmagnesium iodide (3 M in diethyl ether, 0.2 mL, 0.6 mmol) were again added. The reaction mixture was stirred at RT for 2 hours. LCMS analysis still showed some starting ester left. An additional 2 equivalents of methylmagnesium iodide (3 M in diethyl ether, 0.2 mL, 0.6 mmol) were again added at RT, and the stirring was continued for 1 hour. The reaction mixture was quenched with a saturated aqueous solution of NH₄Cl and extracted with ethyl acetate. The organic phase was washed with a saturated aqueous solution of NaHCO₃, dried over sodium sulfate, filtered and concentrated under reduced pressure. The tertiary alcohol compound was used as such without any further purification.

Step 2: 2-(5-amino-1-phenyl-pyrazol-3-yl)propan-2-ol

Trifluoroacetic acid (0.3 mL, 3.9 mmol) was added to a solution of the tertiary alcohol from the previous step (96 mg, 0.3 mmol) in DCM (3 mL). The solution was stirred at RT for 1.5 hours. Trifluoroacetic acid (0.3 mL, 3.9 mmol) was added again, and the solution was heated at 35° C. for 2 hours. The reaction mixture was cooled down to RT, diluted with DCM and washed twice with a saturated aqueous solution of NaHCO₃. The organic phase was separated using a phase separator and concentrated in vacuo to give the titled compound.

Synthesis of AMP68: 5-amino-N-methyl-1-phenyl-pyrazole-3-carboxamide

Step 1: 5-(tert-butoxycarbonylamino)-1-phenyl-pyrazole-3-carboxylic acid

A solution of AMP51B (300 mg, 0.9 mmol) in 2 N NaOH (2 mL, 4 mmol) and ethanol (4.5 mL) was heated at 70° C. for 3 hours. The reaction mixture was acidified to pH 5-6 and extracted with DCM. The organic phase was separated using a phase separator and concentrated under reduced pressure. The intermediate carboxylic acid was used as such without any further purification.

Step 2: tert-butyl N-[5-(methylcarbamoyl)-2-phenyl-pyrazol-3-yl]carbamate

A suspension of EDC.HCl (126 mg, 066 mmol), the carboxylic acid from the previous step (200 mg, 0.66 mmol), and HOBt (107 mg, 0.8 mmol) in DCM (3 mL) was stirred at 0° C. for 15 minutes. 2 M Methylamine in methanol (1 mL, 2 mmol) was added, and the stirring was continued at RT for 20 hours. The solution was diluted with DCM and washed with water. The organic phase was separated using a phase separator, and the volatiles were removed under reduced pressure. The intermediate methyl amide was used as such without any further purification.

Step 3: 5-amino-N-methyl-1-phenyl-pyrazole-3-carboxamide

Trifluoroacetic acid (0.6 mL, 7.8 mmol) was added to a solution of the compound from Step 2 (210 mg, 0.66 mmol) in DCM (6 mL). The solution was stirred at RT for 1.5 hours. Trifluoroacetic acid (0.3 mL, 3.9 mmol) was added again, and the solution was heated at 35° C. for 2 hours. The reaction mixture was cooled down to RT, diluted with DCM and washed twice with a saturated aqueous solution of NaHCO₃. The organic phase was separated using a phase separator and concentrated in vacuo to give the titled compound.

Synthesis of AMP74: 5-amino-1-phenyl-pyrazole-3-carboxamide

Step 1: tert-butyl N-(5-carbamoyl-2-phenyl-pyrazol-3-yl)carbamate

AMP51B (200 mg, 0.6 mmol) in 7 N ammonia in methanol (1 mL) was heated at 70° C. for 5 hours. The reaction mixture was cooled to RT, and the volatiles were removed under reduced pressure. The intermediate carboxamide was used as such without any further purification.

Step 2: 5-amino-1-phenyl-pyrazole-3-carboxamide

Trifluoroacetic acid (0.6 mL, 7.8 mmol) was added to a solution of the compound from Step 1 (181 mg, 0.6 mmol) in DCM (6 mL). The solution was stirred at RT for 1.5 hours. Trifluoroacetic acid (0.3 mL, 3.9 mmol) was added again, and the solution was heated at 35° C. for 2 hours. The reaction mixture was cooled down to RT, diluted with DCM and washed twice with a saturated aqueous solution of NaHCO₃. The organic phase was separated using a phase separator and concentrated in vacuo to give the titled compound.

Synthesis of AMP86: 5-(methylaminomethyl)-2-phenyl-pyrazol-3-amine

Step 1: tert-butyl N-(5-formyl-2-phenyl-pyrazol-3-yl)carbamate

A solution of AMP51B (842 mg, 2.5 mmol) in DCM (8 mL), under nitrogen atmosphere was cooled down to −78° C. 1 M Diisobutylaluminum hydride in toluene (3.3 mL, 3.3 mmol) was added dropwise to the solution, and the stirring at −78° C. was continued for 3 hours. 1 M Diisobutylaluminum hydride in toluene (3.3 mL, 3.3 mmol) is again added and the stirring at −78° C. was continued for another 2 hours. Methanol was added, and the reaction mixture was stirred for 30 minutes warming to RT. 1 M HCl was added, and the reaction mixture was extracted with DCM. The organic phase was separated using a phase separator and concentrated under reduced pressure. The aldehyde compound was used as such without any further purification.

Step 2: tert-butyl N-[5-(methylaminomethyl)-2-phenyl-pyrazol-3-yl]carbamate

A solution of 2 M methyl amine in THF (0.2 mL, 0.4 mmol) was added at RT to a stirring solution of the aldehyde from Step 1 (100 mg, 0.35 mmol) in methanol (2 mL). After 16 hours, sodium borohydride (13 mg, 0.35 mmol) was added, and the stirring at RT was continued for 5 hours. 1 M HCl was added to the reaction mixture, and the two phases were separated. The aqueous phase was basified with a solution of 2 N NaOH and extracted with DCM. The organic phase was filtered through a phase separator and concentrated under reduced pressure to give the methylamine.

Step 3: 5-(methylaminomethyl)-2-phenyl-pyrazol-3-amine

Trifluoroacetic acid (0.3 mL, 3.9 mmol) was added to a solution of the methylamine from Step 2 (106 mg, 0.35 mmol) in DCM (3 mL). The solution was stirred at 35° C. for 2.5 hours. The reaction mixture was cooled down to RT, diluted with DCM and washed twice with a saturated aqueous solution of NaHCO₃. The organic phase was separated using a phase separator and concentrated in vacuo to give the titled compound.

TABLE V List of aminopyrazoles Int Structure Name SM method MW Mes 70373- 98-7

5-Amino-1- phenyl-1,2- dihydro-pyrazol- 3-one 175 826-85- 7

2-Phenyl-2H- pyrazol-3- ylamine 159 1131- 18-6

5-Methyl-2- phenyl-2H- pyrazol-3- ylamine 173 345-07- 3

5-Methyl-2-(3- trifluoromethyl- phenyl)-2H- pyrazol-3- ylamine 241 866472- 29-9

2-(3-Chloro-4- methyl- phenyl)-5- methyl-2H- pyrazol-3- ylamine 221 380569- 79-0

2-(2,4- Difluoro- phenyl)-5- methyl-2H- pyrazol-3- ylamine 209 123279 6-65-4

2-(3,5- Difluoro- phenyl)-5- methyl-2H- pyrazol-3- ylamine 209 890010- 89-6

2-(3,5- Dimethyl- phenyl)-5- methyl-2H- pyrazol-3- ylamine 201 92721- 83-0

5-Methyl-2-m- tolyl-2H- pyrazol-3- ylamine 187 56547- 82-1

2-Cyclohexyl- 5-methyl-2H- pyrazol-3- ylamine 179 40401- 41-0

2-(3-Chloro- phenyl)-5- methyl-2H- pyrazol-3- ylamine 207 105438- 45-7

2-(3-Fluoro- phenyl)-5- methyl-2H- pyrazol-3- ylamine 191 497141- 59-0

5-Methyl-2-(4- trifluoromethoxy- phenyl)- 2H-pyrazol-3- ylamine 257 92721- 94-3

2-(3-Methoxy- phenyl)-5- methyl-2H- pyrazol-3- ylamine 203 3524- 36-5

2-Isobutyl-5- methyl-2H- pyrazol-3-yl amine 153 1124- 16-9

2-Isopropyl-5- methyl-2H- pyrazol-3- ylamine 139 436088- 86-7

5-Amino-1- cyclohexyl- 1H-pyrazol-3- ol 181 124716 9-18-1

5-Amino-1-(4- fluorophenyl)- 1H-pyrazol-3- ol 193 AMP01

5-Methyl-2-(3- trifluorometho xy-phenyl)- 2H-pyrazol-3- ylamine 133115- 55-6, 1118-61-2 E1 Specific example 257 258 AMP02

2-(3,4- Difluoro- phenyl)-5- methyl-2H- pyrazol-3- ylamine 161886- 22-2, 1118-22-2 E1 209 210 AMP03

2-(3-Fluoro- 5-methoxy- phenyl)-5- methyl-2H- pyrazol-3- ylamine ArH03, 1118-61-2 E4 221 222 AMP04

5-Isopropyl-2- phenyl-2H- pyrazol-3- ylamine 100-63-0, 29509-06- 6 E3 201 202 AMP05

2-(3-Bromo- phenyl)-5- isopropyl-2H- pyrazol-3- ylamine 27246-81- 7, 29509- 06-6 E2 280 281 AMP06

2-(3- Dimethylamino- phenyl)-5- isopropyl-2H- pyrazol-3- ylamine ArH01, 29509-06- 6 E4 Specific example 244 245 AMP07

5-Isopropyl-2- m-tolyl-2H- pyrazol-3- ylamine 637-04-7, 29509-06- 6 E2 215 216 AMP08

5-Isopropyl-2- (3- trifluoromethyl- phenyl)-2H- pyrazol-3- ylamine 368-78-5, 29509-06- 6 E3 269 270 AMP09

2-(3,5- Difluoro- phenyl)-5- isopropyl-2H- pyrazol-3- ylamine 134993- 88-7, 29509-06- 6 E2 237 238 AMP10

5-Isopropyl-2- (3-morpholin- 4-yl-phenyl)- 2H-pyrazol-3- ylamine ArH02, 29509-06- 6 E4 286 287 AMP11

5-Isopropyl-2- (3-pyrrolidin- 1-yl-phenyl)- 2H-pyrazol-3- ylamine AMP05 E6 Specific example 270 271 AMP12

2-(3-Fluoro- phenyl)-5- isopropyl-2H- pyrazol-3- ylamine 502496- 27-7, 2950906- 6 E2 219 220 AMP13

2-(4-Fluoro- phenyl)-5- isopropyl-2H- pyrazol-3- ylamine 823-85-8, 29509-06- 6 E2 219 220 AMP14

2-(2,4- Difluoro- phenyl)-5- isopropyl-2H- pyrazol-3- ylamine 51523-79- 6, 29509- 06-6 E2 237 238 AMP15

2-Cyclopropyl- 5-methyl-2H- pyrazol-3- ylamine 213764- 25-1, 1118-61-2 E1 137 138 AMP16

5-Isopropyl-2- (6-methoxy- pyridin-3-yl)- 2H-pyrazol-3- ylamine 179543- 88-5, 29509-06- 6 E2 232 233 AMP17

2-(6-Fluoro- pyridin-2-yl)- 5-isopropyl- 2H-pyrazol-3- ylamine ArH04, 29509-06- 6 E4 220 221 AMP18

[6-(5-Amino- 3-isopropyl- pyrazol-1-yl)- pyridin-2-yl]- dimethyl- amine AMP17 Specific example 245 246 AMP19

5-Isopropyl-2- (6-morpholin- 4-yl-pyridin-2- yl)-2H- pyrazol-3- ylamine AMP17 Specific example 287 288 AMP20

2-(2-Chloro- pyridin-4-yl)- 5-isopropyl- 2H-pyrazol-3- ylamine ArH05, 29509-06- 6 E4 237 238 AMP21

5-Isopropyl-2- (2-morpholin- 4-yl-pyridin-4- yl)-2H- pyrazol-3- ylamine AMP20 E5 287 288 AMP22

5-Isopropyl- 2-(2-pyrrolidin- 1-yl-pyridin-4- yl)-2H- pyrazol-3- ylamine AMP20 Specific example E5 271 272 AMP23

2-Cyclohexyl- 5-isopropyl- 2H-pyrazol-3- ylamine 30929-57- 8, 29509- 06-6 E2 207 208 AMP24

2-(4,4- Difluoro- cyclohexyl)-5- isopropyl-2H- pyrazol-3- ylamine H02, 29509-06- 6 E3 243 244 AMP25

5-Isopropyl-2- (tetrahydro- pyran-3-yl)- 2H-pyrazol-3- ylamine H01, 29509-06- 6 E3 209 210 AMP26

2-Cyclopentyl- 5-isopropyl- 2H-pyrazol-3- ylamine 24214-72- 0, 29509- 06-6 E3 Specific example 193 194 AMP27

5-Isopropyl-2- (tetrahydro- furan-3-yl)- 2H-pyrazol-3- ylamine H03, 29509-06- 6 E3 195 196 AMP28

2-(2,4- Dimethoxy- benzyl)-5- isopropyl-2H- pyrazol-3- ylamine H04, 29509-06- 6 E2 275 276 AMP29

5-Cyclobutyl- 2-phenyl-2H- pyrazol-3- ylamine 59-88-1, CK01 E2 Specific example 213 214 AMP30

2-(3-Bromo- phenyl)-5- cyclobutyl-2H- pyrazol-3 ylamine 27246-81- 7, CK01 E3 292 293 AMP31

5-Cyclobutyl- 2-(3- pyrrolidin-1- yl-phenyl)-2H- pyrazol-3- ylamine AMP30 E6 282 283 AMP32

2-(2-Chloro- pyridin-4-yl)- 5-cyclobutyl- 2H-pyrazol-3- ylamine 700811- 29-6, CK01 E3 248 249 AMP33

5-Cyclobutyl- 2-(2- morpholin-4- yl-pyridin-4- yl)-2H- pyrazol-3- ylamine AMP32 E5 299 300 AMP34

5-Cyclobutyl- 2-(2- pyrrolidin-1- yl-pyridin-4- yl)-2H- pyrazol-3- ylamine AMP32 E5 283 284 AMP35

5-Cyclobutyl- 2-cyclohexyl- 2H-pyrazol-3- ylamine 30929-57- 8, CK01 E2, Specific Example 219 220 AMP36

5-Cyclobutyl- 2-(2,4- dimethoxy- benzyl)-2H- pyrazol-3- ylamine H04, CK01 E2 287 288 AMP37

5-tert-Butyl-2- cyclopentyl- 2H-pyrazol-3- ylamine 24214-72- 0, 599917- 51-2 E2 207 208 AMP38

3-(5-Amino-1- cyclohexyl- 1H-pyrazol-3- yl)-azetidine-1- carboxylic acid tert-butyl ester 30929-57- 8, 887594- 13-0 E2 320 321 AMP39

2-Cyclohexyl- 5-cyclopropyl- 2H-pyrazol-3- ylamine 30929-57- 8, 118431- 88-2 E2 205 206 AMP40

3-[5-Amino-1- (3,5-difluoro- phenyl)-1H- pyrazol-3-yl]- azetidine-1- carboxylic acid tert-butyl ester 134993- 88-7, 887594- 13-0 E2 350 295¹ AMP41

5-(1-Methyl- cyclobutyl)-2- phenyl-2H- pyrazol-3- ylamine 100-63-0, CK02 E3 227 228 AMP42

5-(3-Methoxy- cyclobutyl)-2- phenyl-2H- pyrazol-3- ylamine 59-88-1, CK03 E2 243 AMP43

5-(3,3- Difluoro- cyclobutyl)-2- phenyl-2H- pyrazol-3- ylamine 59-88-1, 1234616- 26-2 E2 249 AMP44

5-(3,3- Dimethyl- cyclobutyl)-2- phenyl-2H- pyrazol-3- ylamine 59-88-1, CK04 E2 241 AMP45

5-(3-Fluoro- cyclobutyl)-2- phenyl-2H- pyrazol-3- ylamine 59-88-1, CK05 E2 231 AMP46

5-(3-Methyl- cyclobutyl)-2- phenyl-2H- pyrazol-3- ylamine 59-88-1, CK06 E2 227 AMP47

2-Cyclopentyl- 5-methyl- pyrazol-3- amine 24214-72- 0, 1118- 61-2 E1 165 AMP48 61255- 82-1

3-(5-Amino-3- methyl- pyrazol-1- yl)propanenitrile 150 AMP49 76606- 39-8

2-(4- Fluorophenyl)- 5-methyl- pyrazol-3- amine 191 AMP50

5-Methyl-2-[5- (trifluorometh yl)-1H- pyrazol-3- yl]pyrazol-3- amine 1418117- 75-5, 1118-61-2 E1 231 232 AMP51 866837- 96-9

Ethyl 5-amino- 1-phenyl- pyrazole-3- carboxylate 231 AMP51 B

Ethyl 5-(tert- butoxycarbonyl amino)-1- phenyl- pyrazole-3- carboxylate 866837- 96-9 Specific example 331 332 AMP52 956329- 14-9

2-(3- Bromophenyl)- 5-methyl- pyrazol-3- amine 252 AMP53

(5-Amino-1- phenyl- pyrazol-3- yl)methanol 866837- 96-9 (AMP51) Specific example 189 190 AMP54 124707 5-24-6

5-Methyl-2- tetrahydropyran- 4-yl-pyrazol- 3-amine 181 AMP55

5-Methyl-2-(3- morpholinophenyl) pyrazol-3- amine H05, 1118-61-2 E1 258 259 AMP56

2-[3- (Dimethylamino) phenyl]-5- methyl- pyrazol-3- amine 940924- 81-2, 1118-61-2 E1 216 217 AMP57

5-Methyl-2-(3- methylsulfonyl phenyl)pyrazol- 3-amine 312303- 93-8, 1118-61-2 E1 251 252 AMP58 3524- 43-4

5-Methyl-2-(1- methyl-4- piperidyl)pyrazol- 3-amine 194 AMP59

5-tert-Butyl-2- phenyl- pyrazol-3- amine 100-63-0, 59997-51- 2 E2 215 216 AMP60

2-(2-Chloro-4- pyridyl)-5- isopropyl- pyrazol-3- amine 700811- 29-6, 29509-06- 6 E2 236 237 AMP61

5-Isopropyl-2- [4- (trifluoromethoxy) phenyl]pyra zol-3-amine 13957-54- 5, 29509- 06-6 E2 285 286 AMP62

2-(3,5- Dichlorophenyl)- 5-methyl- pyrazol-3- amine 39943-56- 1, 1118- 61-2 E1 242 243 AMP63

3-(5-Amino-3- methyl- pyrazol-1- yl)benzenesul- fonamide 131774- 72-6, 1118-61-2 E1 252 253 AMP64

5-Methyl-2-(1- methylpyrazol- 4-yl)pyrazol-3- amine 268521- 80-7, 1118-61-2 E1 177 178 AMP65

tert-Butyl 3-(5- amino-1- phenyl- pyrazol-3- yl)azetidine-1 carboxylate 100-63-0, 887594- 13-0 E2 314 315 AMP66

2-(5-Amino-1- phenyl- pyrazol-3- yl)propan-2-ol AMP51B Specific example 217 218 AMP67

3-(5-Amino-3- isopropyl- pyrazol-1- yl)benzonitrile 17672-26- 3, 29509- 06-6 E2 226 227 AMP68

5-Amino-N- methyl-1- phenyl- pyrazole-3- carboxamide AMP51B Specific example 216 217 AMP69

2-(5-Amino-1- phenyl- pyrazol-3-yl)- 2-methyl- propan-1-ol 100-63-0, 489432- 33-9 E2 231 232 AMP70

2-(2-Fluoro-4- pyridyl)-5- methyl- pyrazol-3- amine 837364- 87-1, 1118-61-2 E1 192 193 AMP71

4-(5-Amino-3- methyl- pyrazol-1-yl)- 1H-pyridin-2- one 106689- 41-2, 1118-61-2 E1 190 191 AMP72

3-(5-Amino-3- methyl- pyrazol-1- yl)benzamide 473927- 51-4, 1118-61-2 E1 216 217 AMP73

2-(6-Methoxy- 3-pyridyl)-5- methyl- pyrazol-3- amine 160664- 95-9, 1118-61-2 E1 204 205 AMP74

5-Amino-1- phenyl- pyrazole-3- carboxamide AMP51B Specific example 202 203 AMP75

tert-Butyl 2-(5- amino-1- phenyl- pyrazol-3- yl)pyrrolidine- 1-carboxylate 100-63-0, 173690- 69-2 E2 328 329 AMP77

5- (Methoxymeth yl)-2-phenyl- pyrazol-3- amine 100-63-0, 739366- 02-0 E2 203 204 AMP78

5-(1- Methylcyclo propyl)-2- phenyl- pyrazol-3- amine 100-63-0, 88485-78- 3 E3 213 214 AMP79

5-tert-Butyl-2- cyclohexyl- pyrazol-3- amine 30929-57- 8, 599917- 51-2 E2 221 222 AMP80

2-Phenyl-5- tetrahydrofuran- 2-yl-pyrazol- 3-amine 100-63-0, CK07 E2 229 230 AMP81

5-Isopropyl-2- (5-morpholino- 3- pyridyl)pyrazol- 3-amine ArH06, 29509-06- 6 E4 287 288 AMP82

2-(4-Chloro-2- pyridyl)-5- isopropyl- pyrazol-3- amine ArH07, 29509-06- 6 E4 236 237 AMP83

2-(3,4- Difluorophenyl)- 5-isopropyl- pyrazol-3- amine 875664- 54-3, 29509-06- 6 E2 273 274 AMP84

5-Isopropyl-2- [3- (trifluoromethyl) phenyl]pyraz ol-3-amine 368-78-5, 29509-06- 6 E2 269 270 AMP85

5-(3- Methyloxetan- 3-yl)-2-phenyl- pyrazol-3- amine 100-63-0, CK08 E2 229 230 AMP86

5- (Methylamino methyl)-2- phenyl- pyrazol-3- amine AMP51B Specific example 202 203 AMP87

2-(3- Methoxyphenyl)- 5-methyl- pyrazol-3- amine 39232-91- 2, 1118- 61-2 E1 203 204 AMP88 70373- 98-7

5-Amino-1- phenyl-1,2- dihydro-3H- pyrazol-3-one 175 AMP89

2-(3- Benzyloxycyclo- hexyl)-5- isopropyl- pyrazol-3- amine H06, 29509-06- 6 E3 313 314 AMP90

Benzyl 4-(5- amino-3- isopropyl- pyrazol-1- yl)piperidine- 1-carboxylate H07, 29509-06- 6 E3 342 343 AMP91

Benzyl 3-(5- amino-3- isopropyl- pyrazol-1- yl)pyrrolidine- 1-carboxylate H08, 29509-06- 6 E3 328 329 AMP92

Benzyl 3-(5- amino-3- isopropyl- pyrazol-1- yl)piperidine- 1-carboxylate H09, 29509-06- 6 E3 342 343 AMP93

3-Cyclobutyl- 1-(4- fluorophenyl)- 1H-pyrazol-5- amine 118431- 89-3, 823- 85-8 Specific example 231 232 AMP94

1-tert-Butyl-3- cyclobutyl-1H- pyrazol-5- amine 7400-27- 3, 118431- 89-3 Specific example 193 194 AMP95

1-Cyclohexyl- 3-[(propan-2- yl)oxy]-1H- pyrazol-5- amine 436088- 86-7 E7 223 224 AMP96

1-(4- Fluorophenyl)- 3-[(propan-2- yl)oxy]-1H- pyrazol-5- amine 1247169- 18-1 E7, Specific example 235 236 ¹(M − tBu + H)⁺

Method F: Synthesis of Aldehydes by SN—Ar

-   A is either CH or N -   LG is F, Cl, or Br

A solution of the aldehyde (1 equiv), the amine (1.3 to 2 equiv) and the base (DIPEA or K₂CO₃) (2 equiv) is prepared in acetonitrile, DMSO or DMA. This mixture is heated under thermal conditions or under microwave irradiations at a temperature ranging from 85° C. to 150° C. The reaction is worked up either by filtration of the base when needed or by diluting the reaction mixture with ethyl acetate or DCM and washing the organic phase with water and brine. In all cases, the organic phase is concentrated under reduced pressure, and the crude residue is used as such or purified either by flash column chromatography or precipitation to give the titled compound.

Illustrative synthesis of ALD02: 5′-Formyl-3,4,5,6-tetrahydro-2H-[1,2′]bipyridinyl-4-carbonitrile

A solution of 2-chloropyridine-5-carboxaldehyde (CAS: 23100-12-1, 25.1 g, 177.4 mmol), 4-cyanopiperidine (CAS: 4395-98-6, 25.4 g, 230.6 mmol) and DIPEA (62 mL, 354.7 mmol) in acetonitrile (250 mL) was refluxed for 20 hours. The reaction mixture was cooled to RT, and the mixture was concentrated under reduced pressure. The residue was dissolved in DCM (500 mL) and washed successively with a saturated aqueous solution of Na₂CO₃ (250 mL) and brine (250 mL). The organic phase was stirred for 2 minutes with 10 g of silica gel, dried over sodium sulfate, filtered and concentrated under reduced pressure. The resulting mixture was dissolved in DCM (150 mL) and poured into a stirring solution of diisopropyl ether (1.5 L). The mixture was stirred vigorously for 4 hours. The precipitate was collected by filtration, washed with diisopropyl ether, and dried at 40° C. under reduced pressure to give the titled compound.

TABLE VI List of aldehydes Int. Structure Name SM method MW Mes ALD01

6-[(2-Methoxy- ethyl)-methyl- amino]- pyridine-3- carbaldehyde 23100- 12-1 F 194 195 ALD02

5′-Formyl-3,4,5,6- tetrahydro-2H-[1, 2′]bipyridinyl-4- carbonitrile 23100- 12-1 F Specific example 215 216 ALD03

6-[Methyl- (tetrahydro-pyran- 4-yl)-amino]- pyridine-3- carbaldehyde 23100- 12-1 F 220 221 ALD04

4-[(2-Methoxy- ethyl)-methyl- amino]- benzaldehyde 459-57- 4 F 193 194 ALD05

1-(4-Formyl- phenyl)-piperidine- 4-carbonitrile 459-57- 4 F 214 215 ALD06

2-[Methyl- (tetrahydro-pyran- 4-yl)-amino]- pyrimidine-5- carbaldehyde 933702- 55-7 F 221 222 ALD07

1-(5-Formyl- pyrimidin-2-yl)- piperidine-4- carbonitrile 933702- 55-7 F 216 217 ALD08

4-[Methyl- (tetrahydro-pyran- 4-yl)-amino]- benzaldehyde 459-57- 4 F 219 220 ALD09

2-[(2-Methoxy- ethyl)-methyl- amino]-pyrimidine- 5-carbaldehyde 933702- 55-7 F 195 196 ALD10

6-Dimethylamino- pyridine-3- carbaldehyde 23100- 12-1 F 150 151 ALD11 1204- 86-0

4- morpholinobenzal- dehyde 191 ALD12

6-[bis(2- methoxyethyl)ami- no]pyridine-3- carbaldehyde 23100- 12-1 F 238 239

Methods G1-G3: Synthesis of Alkylidene Pyruvate Method G1: Synthesis of Alkylidene Pyruvate

-   A is either N or CH -   A′ is either R^(e) or L¹-G^(3C) as described in the Summary

A solution of potassium hydroxide (from 1.5 to 2 equiv) in water is added dropwise at 0° C. to a solution of aldehyde (1 equiv) and pyruvic acid (CAS 127-17-3, from 1 eq to 1.5 equiv) in methanol. The reaction is warmed up to RT and then heated at 40° C. for 1 h to several days. Then the reaction mixture undergoes one of the following processes:

-   -   Either the formed precipitate is collected by filtration,         suspended in an aqueous acidic solution, collected by filtration         again, and dried in vacuo to give the titled compound.     -   Or alternatively, methanol is removed in vacuo, and the         resulting suspension is filtered. The solid is taken up in water         and either ethyl acetate or dichloromethane and acidified to         pH=3-5 with either acetic acid or an aqueous solution of 2 M         HCl. The two phases are separated, and the aqueous phase is         extracted with either ethyl acetate or dichloromethane. The         combined organic phases are washed with water and brine, dried         over MgSO₄, filtered and concentrated in vacuo to afford the         titled compound which is used as such or further purified by         precipitation.

Illustrative synthesis of ALP19: (E)-4-(4-Bromo-phenyl)-2-oxo-but-3-enoic acid

A solution of potassium hydroxide (6.9 g, 121.6 mmol) in water (45 mL) was added at 0° C. to a stirring solution of 4-bromobenzaldehyde (CAS 1122-91-4, 15 g, 81.1 mmol) and pyruvic acid (CAS 127-17-3, 5.7 mL, 81.1 mmol) in methanol (105 mL) over a 5 minutes period. The reaction mixture was then heated at 40° C. for 4 hours, cooled down to RT and poured into ice/water (300 mL). The precipitate was stirred for 10 minutes, collected by filtration, washed with water and n-heptane, and air dried for 1 hour. The solid was suspended in aqueous 2 N HCl and stirred for 10 minutes. The precipitate was collected by filtration and dried at 40° C. under reduced pressure to afford the titled compound.

Method G2: Synthesis of Alkylidene Pyruvate

-   A is either N or CH -   A′ is either R^(e) or L¹-G^(3C) as described in the Summary

Triflic acid (CAS 1493-13-6, from 1.35 eq to 2.5 equiv) is added dropwise to a solution of aldehyde (1 equiv), triethyl orthoformate (CAS 122-51-0, from 1.1 eq to 1.3 equiv) and ethyl pyruvate (CAS 617-35-6, from 1.5 to 3.5 equiv) in chloroform. The solution is refluxed for 30 minutes to 24 h. The reaction mixture is cooled down to RT, diluted with dichloromethane, basified with a saturated aqueous solution of Na₂CO₃ or NaHCO₃. The two phases are separated, and the aqueous phase is extracted with dichloromethane. The combined organic phases are dried over sodium sulfate, filtered and concentrated under reduced pressure. This crude mixture is purified either by flash chromatography on silica gel or by precipitation to afford the titled compound.

Illustrative synthesis of ALP09: ethyl(E)-4-[6-(4-cyano-1-piperidyl)-3-pyridyl]-2-oxo-but-3-enoate

Triflic acid (CAS 1493-13-6, 26.7 mL, 301 mmol) was added dropwise to a solution of intermediate ALD02 (32.4 g, 150.5 mmol), triethyl orthoformate (CAS 122-51-0, 32.6 g, 195.7 mmol) and ethyl pyruvate (CAS 617-35-6, 41.7 mL, 376.3 mmol) in chloroform (180 mL). The solution was refluxed for 30 minutes and then cooled to RT. The reaction mixture was diluted with DCM (500 mL) and washed successively with a saturated aqueous solution of Na₂CO₃ (400 mL) and brine (400 mL). The organic phase was dried over sodium sulfate, filtered and concentrated under reduced pressure. The crude sample was purified by flash column chromatography on silica gel eluting with a gradient of n-heptane/ethyl acetate to yield the titled compound.

Method G3: Synthesis of Alkylidene Pyruvate

In a round bottom flask, under a nitrogen atmosphere, a suspension of 4-ethynylbenzene derivative (1 equiv.), 50% ethyl glyoxalate in toluene (2 equiv), morpholine ([110-91-8], 2 equiv), copper (I) bromide ([7787-70-4], 0.5 equiv) in dioxane is heated to 85° C. for 3 to 20 hours. The reaction mixture is cooled to RT, and the solvent was evaporated under reduced pressure. The residue is suspended in a mixture of DCM or DCM/2-propanol (95/5) and is washed twice with water. The organic phase is dried over sodium sulfate, filtered and concentrated under reduced pressure. The crude sample is purified by flash chromatography eluting with ethyl acetate/n-heptane/DCM.

Illustrative synthesis of ALP36: ethyl 4-(4-formylphenyl)-2-oxobut-3-enoate

In a round bottom flask, under a nitrogen atmosphere, a suspension of 4-ethynylbenzaldehyde ([63697-96-1], 5 g, 38.4 mmol), 50% ethyl glyoxalate in toluene ([924-44-7], 15.7 mL, 15.7 g, 76.8 mmol), morpholine ([110-91-8], 6.7 mL, 76.8 mmol), copper(I) bromide ([7787-70-4], 2.8 g, 19.2 mmol) in dioxane (50 mL) was heated to 85° C. for 3 hours. The reaction mixture was cooled to RT, and the volatiles were removed under reduced pressure. The residue was suspended in a mixture of DCM/2-propanol (200 mL, 95/5) and washed twice with water (50 mL). The organic phase was dried over sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by flash chromatography eluting with ethyl acetate/n-heptane to yield the titled compound.

Synthesis of ALP 31: (E)-4-[4-(1-methyl-3,6-dihydro-2H-pyridin-4-yl)phenyl]-2-oxo-but-3-enoic acid

Nitrogen was bubbled for 5 minutes into a suspension of ALP19 (100 mg, 0.4 mmol), 1-methyl-1,2,3,6-tetrahydropyridine-4-boronic acid pinacol ester (CAS: 454482-11-2, 109 mg, 0.5 mmol), Pd(dppf)Cl₂.DCM (20 mg, 0.02 mmol), and cesium carbonate (240 mg, 0.7 mmol) in dioxane/water (2/1 v/v, 2 mL). The reaction mixture was heated at 90° C. for 1 hour and cooled to RT. The volatiles were removed under reduced pressure, and the crude residue was suspended in water (20 mL). The aqueous solution was acidified with a citric acid solution to pH 5. The precipitate was filtered, washed with water and dried at 40° C. under reduced pressure to give the titled compound as the citrate salt. No further purification was performed and the compound was used as such in the next step.

Synthesis of ALP38: 4-Cyano-4-[4-((E)-3-ethoxycarbonyl-3-oxo-propenyl)-phenyl]-piperidine-1-carboxylic acid tert-butyl ester

Step 1: 4-Cyano-4-{4-[(triisopropylsilanyl)-ethynyl]-phenyl}-piperidine-1-carboxylic acid tert-butyl ester

Nitrogen was bubbled for 5 minutes through a suspension of tert-butyl 4-(4-bromophenyl)-4-cyanopiperidine-1-carboxylate ([847615-14-9], 547 mg, 1.5 mmol), tetrakis(triphenylphosphine)palladium(O) ([14221-01-3], 90 mg, 77 μmol), copper(I) iodide ([7681-65-4], 8 mg, 42 μmol), lithium chloride ([7447-41-8], 8 mg, 189 μmol), and (triisopropylsilyl)acetylene ([89343-06-6], 670 μL, 3 mmol) in triethylamine (8 mL). The tube was sealed and heated at 100° C. for 6 hours. The mixture was then concentrated under reduced pressure, and the residue was partitioned between ethyl acetate and water. The organic phase was dried over sodium sulfate, filtered and concentrated in vacuo. The residue was purified by flash column chromatography eluting with ethyl acetate/n-heptane to give the titled compound.

Step 2: 4-Cyano-4-(4-ethynyl-phenyl)-piperidine-1-carboxylic acid tert-butyl ester

The compound from Step 1 (700 mg, 1.5 mmol) was dissolved in anhydrous THF (10 mL) and 1 M tetra-n-butylammonium fluoride in THF (1.7 mL, 1.7 mmol) was added. The reaction mixture was stirred at RT for 2 hours and then concentrated under reduced pressure. The residue was partitioned between ethyl acetate and water. The organic phase was dried over sodium sulfate, filtered and concentrated in vacuo. The residue was purified by flash column chromatography eluting with ethyl acetate/n-heptane to give the titled compound.

Step 3: 4-Cyano-4-[4-((E)-3-ethoxycarbonyl-3-oxo-propenyl)-phenyl]-piperidine-1-carboxylic acid tert-butyl ester

In a round bottom flask, under a nitrogen atmosphere, a suspension of the compound from Step 2 (270 mg, 0.58 mmol), 50% ethyl glyoxalate in toluene ([924-44-7], 232 μL, 1.16 mmol), morpholine ([110-91-8], 101 μL, 1.16 mmol), and copper(I) bromide ([7787-70-4], 42 mg, 0.29 mmol) in dioxane (5 mL) was heated to 85° C. for 20 hours. The reaction mixture was cooled down to RT and 50% ethyl glyoxalate in toluene ([924-44-7], 232 1.16 mmol), morpholine ([110-91-8], 101 μL, 1.16 mmol), and copper(I) bromide ([7787-70-4], 42 mg, 0.29 mmol) were added again, and the sealed tube was heated at 100° C. for 1 hour. The reaction mixture was cooled to RT and concentrated under reduced pressure. The residue was suspended in DCM (20 mL) and washed with water (15 mL). The organic phase was dried over sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by flash chromatography eluting with ethyl acetate/n-heptane to yield the titled compound.

Synthesis of ALP 39: methyl(3E)-4-(4-bromophenyl)-2-oxobut-3-enoate

EDC.HCl ([25952-538], 7.3 g, 38 mmol) was added at RT to a stirred solution of ALP19 (8.05 g, 32 mmol) in a mixture of dichloromethane/methanol (1/1; 160 mL). The reaction mixture was stirred at RT for 20 hours. The mixture was diluted with DCM (200 mL) and washed with a saturated aqueous solution of NaHCO3 (100 mL). The aqueous phase was extracted again with DCM (200 mL). The combined organic phases were dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by flash column chromatography eluting with dichloromethane to yield the titled compound.

TABLE VII List of alkylidene pyruvates Int. Structure Name SM method MW Mes ALP01

(E)-4-(4- morpholinophenyl)- 2-oxo-but-3- enoic acid 1204- 86-0 G1 261 262 ALP02

(E)-4-[4- (dimethylamino) phenyl]-2-oxo-but- 3-enoic acid 100-10- 7 G1 219 220 ALP03

(E)-4-[2- (dimethylamino) pyrimidin-5-yl]-2- oxo-but-3-enoic acid 55551- 49-0 G1 221 222 ALP04

(E)-4-(2- morpholino- pyrimidin- 5-yl)-2-oxo- but-3-enoic acid 842974- 69-0 G1 263 264 ALP05

(E)-4-(6- morpholino-3- pyridyl)-2-oxo- but-3-enoic acid 173282- 60-5 G1 262 263 ALP06

(E)-4-(4- methoxyphenyl)- 2-oxo-but-3-enoic acid 123-11- 5 G1 206 207 ALP07

(E)-4-(6-Chloro- pyridin-3-yl)-2- oxo-but-3-enoic acid 23100- 12-1 G1 211- 213 212- 214 ALP08

ethyl (E)-4-[6-[2- methoxyethyl (methyl) amino]-3- pyridyl]-2-oxo- but-3-enoate ALD01 G2 291 292 ALP09

ethyl (E)-4-[6-(4- cyano-1- piperidyl)-3- pyridyl]-2-oxo- but-3-enoate ALD02 G2 Specific example 313 314 ALP10

ethyl (E)-4-[6- [methyl(tetrahydro pyran-4- yl)amino]-3- pyridyl]-2-oxo- but-3-enoate ALD03 G2 318 319 ALP11

ethyl (E)-4-[4-[2- methoxyethyl(meth- yl)amino]phenyl]- 2-oxo-but-3- enoate ALD04 G2 291 292 ALP12

ethyl (E)-4-[4-(4- cyano-1- piperidyl)phenyl]- 2-oxo-but-3- enoate ALD05 G2 312 313 ALP13

ethyl (E)-4-[2- [methyl(tetrahydro pyran-4- yl)amino]pyrimidin- 5-yl]-2-oxo-but- 3-enoate ALD06 G2 319 320 ALP14

ethyl (E)-4-[2-(4- cyano-1- piperidyl)pyrimidin- 5-yl]-2-oxo-but- 3-enoate ALD07 G2 314 315 ALP15

ethyl (E)-4-[4- [methyl(tetrahydro pyran-4- yl)amino]phenyl]- 2-oxo-but-3- enoate ALD08 G2 317 318 ALP16

ethyl (E)-4-[2-[2- methoxyethyl (methyl)amino] pyrimidin- 5-yl]-2-oxo- but-3-enoate ALD09 G2 293 294 ALP17

ethyl (E)-4-(2,6- difluoro-4- methoxy-phenyl)- 2-oxo-but-3- enoate 256417- 10-4 G2 270 271 ALP18

(E)-4-(4- morpholin-4-yl- phenyl)-2-oxo- but-3-enoic acid ethyl ester ALD11 (1204- 86-0) G2 289 290 ALP19

(E)-4-(4-bromo- phenyl)-2-oxo- but-3-enoic acid 1122- 91-4 G1 Specific example 255 255- 257 ALP20

(E)-4-(6- dimethylamino- pyridin-3-yl)-2- oxo-but-3-enoic acid ethyl ester ALD10 G2 248 249 ALP21

(E)-4-(6- dimethylamino- pyridin-3-yl)-2- oxo-but-3-enoic acid ALD10 G1 220 221 ALP22

(E)-4-(2- morpholin-4-yl- pyrimidin-5-yl)-2- oxo-but-3-enoic acid ethyl ester 842974- 69-0 G2 291 292 ALP23

(E)-4-{6-[bis-(2- methoxy-ethyl)- amino]-pyridin-3- yl}-2-oxo-but-3- enoic acid ethyl ester ALD12 G2 336 337 ALP24

(E)-4-(4- acetylamino- phenyl)-2-oxo- but-3-enoic acid ethyl ester 122-85- 0 G2 261 262 ALP25

(E)-4-(4- dimethylamino- phenyl)-2-oxo- but-3-enoic acid ethyl ester 100-10- 7 G2 247 248 ALP26

(E)-4-(6- morpholin-4-yl- pyridin-3-yl)-2- oxo-but-3-enoic acid ethyl ester 173282- 60-5 G2 290 291 ALP27

(E)-4-[4-(4- methylpiperazin- 1-yl)phenyl]-2- oxo-but-3-enoic acid 27913- 99-1 G1 274 275 ALP28

(E)-4-[4-(1,1- dioxo-1,4- thiazinan-4- yl)phenyl]-2-oxo- but-3-enoic acid 27913- 96-8 G1 309 310 ALP29

(E)-2-oxo-4-(4- pyrrolidin-1- ylphenyl)but-3- enoic acid 51980- 54-2 G1 245 246 ALP30

(E)-4-(2-chloro-4- morpholino- phenyl)-2-oxo- but-3-enoic acid 886501- 36-6 G1 295 295- 297 ALP31

(E)-4-[4-[1- methyl-3,6- dihydro-2H- pyridin-4- yl)phenyl]-2-oxo- but-3-enoic acid ALP19 Specific example 271 272 ALP32

(E)-4-(2-methoxy- 4-morpholino- phenyl)-2-oxo- but-3-enoic acid 404009- 68-3 G1 291 292 ALP33

(E)-3-methyl-4-(4- morpholinophenyl)- 2-oxo-but-3- enoic acid 1204- 86-0 G1 275 276 ALP34

(E)-4-(3-bromo-4- morpholino- phenyl)-2-oxo- but-3-enoic acid 404009- 68-3 G1 339 340- 342 ALP35

(E)-2-oxo-4-[4-(1- piperidyl)phenyl] but-3-enoic acid 10338- 57-5 G1 259 260 ALP36

ethyl 4-(4- formylphenyl)-2- oxobut-3-enoate 63697- 96-1 G3 Specific example 232 ALP37

ethyl 4-(4- cyanophenyl)-2- oxobut-3-enoate 3032- 92-6 G3 229 ALP38

4-Cyano-4-[4- ((E)-3- ethoxycarbonyl-3- oxo-propenyl)- phenyl]- piperidine-1- carboxylic acid tert-butyl ester 847615- 14-9 Specific example 412 NA ALP39

methyl (3E)-4-(4- bromophenyl)-2- oxobut-3-enoate ALP19 Specific example 269 268- 270

Methods H1-H3: Synthesis of Halogenated Pyrazolopyridine Method H1: Synthesis of Halogenated Pyrazolopyridine (Route 1) Illustrative synthesis of HP01: ethyl 4-chloro-3-isopropyl-1-(m-tolyl)pyrazolo[3,4-b]pyridine-6-carboxylate

Step 1: 6-Hydroxy-3-isopropyl-1-m-tolyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid ethyl ester

5-Isopropyl-2-m-tolyl-2H-pyrazol-3-ylamine hydrochloride (AMP07, 14.97 g, 59.7 mmol) was dissolved in AcOH (100 mL). Diethyloxalacetate sodium salt (CAS: 40876-98-0, 15 g, 71.6 mmol, 1.2 equiv) was added, and the reaction mixture was refluxed overnight. The reaction mixture was cooled down to RT, poured into water (400 mL) and diluted with ethyl acetate. The two phases were separated, and the aqueous phase was extracted with ethyl acetate. The combined organic layers were concentrated in vacuo, and the resulting residue was taken up twice with cyclohexane (2×200 mL) and concentrated in vacuo again. The residue was suspended in a mixture of ethanol/water (100 mL/20 mL), and the resulting precipitate was collected by filtration and washed with heptane. The solid was dried under vacuum to provide the titled compound.

Step 2: 3-Isopropyl-1-m-tolyl-6-trifluoromethanesulfonyloxy-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid ethyl ester

6-Hydroxy-3-isopropyl-1-m-tolyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid ethyl ester (14.25 g, 42 mmol) was suspended in acetonitrile under nitrogen atmosphere. Pyridine (3.8 mL, 46.2 mmol, 1.1 equiv) was added. The reaction mixture was cooled to 0° C., and trifluoromethanesulfonic anhydride (CAS 358-23-6, 7.8 mL, 46.2 mmol, 1.1 equiv) was added dropwise over 20 min. The reaction mixture was then warmed up to RT over 20 min. Water was added (200 mL), and the suspension was filtered. The solid was washed successively with water and ethanol (40 mL) and then dried in vacuo to afford the titled compound.

Step 3: 6-Iodo-3-isopropyl-1-m-tolyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid ethyl ester

3-Isopropyl-1-m-tolyl-6-trifluoromethanesulfonyloxy-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid ethyl ester (13.0 g, 27.6 mmol) was suspended in acetonitrile. Sodium iodide (20.7 g, 138 mmol, 5 equiv) was added. The reaction mixture was cooled to 0° C., trifluoromethanesulfonic acid (5.4 mL, 60.7 mmol, 2.2 equiv) was added dropwise. The reaction mixture was stirred at RT overnight. At this point, the reaction was not complete and additional trifluoromethanesulfonic acid (2 mL, 22.6 mmol, 0.8 equiv) was added and stirring was continued for 1 hour. Water was added to the reaction mixture, and the suspension was filtered. The solid was washed with ethanol (10 mL) and dried in vacuo to afford the titled compound.

Step 4: 6-Iodo-3-isopropyl-1-m-tolyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid

6-Iodo-3-isopropyl-1-m-tolyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid ethyl ester (8.73 g, 4.63 mmol) was suspended in ethanol (10 mL). An aqueous solution of 2 M sodium hydroxide (10 mL, 20 mmol, 4.3 equiv) was added, and the reaction mixture was stirred at 70° C. until complete conversion. Then the reaction mixture was cooled down to 0° C., and an aqueous solution of 2 M HCl was added until pH<2 was reached. The resulting suspension was filtered, and the solid was dried in vacuo to afford the titled compound.

Step 5: (6-Iodo-3-isopropyl-1-m-tolyl-1H-pyrazolo[3,4-b]pyridin-4-yl)-carbamicacid tert-butyl ester

6-Iodo-3-isopropyl-1-m-tolyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid (8.12 g, 19.3 mmol) was suspended in toluene (43 mL). tert-Butanol (3.1 mL, 32.6 mmol, 2.0 equiv), triethylamine (4.54 mL, 32.6 mmol, 2.0 equiv) and diphenylphosphoryl azide (CAS 26386-88-9, 5 mL, 23.1 mmol, 1.2 equiv) were successively added. The reaction mixture was refluxed for 30 minutes. The reaction mixture was cooled down to RT and partitioned between ethyl acetate and water. The aqueous phase was further extracted with ethyl acetate. The combined organic phases were washed with brine, dried over Na₂SO₄, filtered and concentrated in vacuo. The residue was suspended in ethanol. The resulting precipitate was collected by filtration, washed with ethanol and dried under vacuum to provide the titled compound.

Step 6: (6-Cyano-3-isopropyl-1-m-tolyl-1H-pyrazolo[3,4-b]pyridin-4-yl)-carbamic acid tert-butyl ester

(6-Iodo-3-isopropyl-1-m-tolyl-1H-pyrazolo[3,4-b]pyridin-4-yl)-carbamicacid tert-butyl ester (7.56 g, 15.4 mmol) was solubilized in dry dimethylformamide (20 mL) in a sealed vial. Zinc cyanide (CAS 557-21-1, 1.1 g, 9.2 mmol, 0.6 equiv) was added, and the reaction mixture was degassed with argon (bubbling) for 5 minutes.

Tetrakis(triphenylphosphine)palladium(O) (CAS 14221-01-3, 0.9 g, 0.77 mmol, 0.05 equiv) was added, and the reaction mixture was degassed again with argon (bubbling) for 5 minutes. The vial was sealed, and the reaction mixture was stirred at 110° C. for 2 hour. The reaction mixture was cooled down to room temperature and diluted with water and ethyl acetate. The aqueous phase was further extracted with ethyl acetate. The combined organic phases were washed with brine, dried over Na₂SO₄, filtered and concentrated to a volume of 10 mL. Ethanol (10 mL) was added, and the suspension was stirred at 0° C. for 10 min. The resulting precipitate was collected by filtration, washed with ethanol and dried under vacuum to provide the titled compound.

Step 7: 4-Amino-3-isopropyl-1-m-tolyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid hydrochloride salt

(6-Cyano-3-isopropyl-1-m-tolyl-1H-pyrazolo[3,4-b]pyridin-4-yl)-carbamic acid tert-butyl ester (4.8 g, 12.26 mmol) was suspended in 6 M HCl (50 mL). The reaction mixture was refluxed for 24 h. The reaction mixture was cooled to 0° C., and the obtained suspension was filtered. The solid was washed with diisopropyl ether and dried in vacuo to yield the titled compound.

Step 8: 4-Amino-3-isopropyl-1-m-tolyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid ethyl ester

4-Amino-3-isopropyl-1-m-tolyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid hydrochloride salt (4.23 g, 12.26 mmol) was solubilized in ethanol (150 mL). Thionyl chloride (CAS 7719-09-7, 1.34 mL, 18.39 mmol, 1.5 equiv) was carefully added. The reaction mixture was refluxed for 24 hours. The reaction mixture was cooled down to RT and concentrated in vacuo. The residue was taken up in ethanol (85 mL) and thionyl chloride (CAS 7719-09-7, 2.32 mL, 31.86 mmol, 2.6 equiv) was carefully added at RT. The mixture was refluxed for 6 hours. The reaction mixture was cooled down to RT and concentrated in vacuo. The crude mixture was diluted with ethyl acetate, basified with a saturated solution of sodium hydrogencarbonate. This mixture was filtered through a pad of Celpure® P65. Solids were washed with ethyl acetate. The two phases of the filtrate were separated, and the aqueous fraction was further extracted with ethyl acetate. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The residue was purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate gradient from 95/5 to 80/20) to afford the titled compound.

Step 9: 4-Chloro-3-isopropyl-1-m-tolyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid ethyl ester

Copper(II) chloride (CAS 7447-39-4, 1.045 g, 7.77 mmol, 1.0 equiv) was suspended in acetonitrile (33 mL). Isopentylnitrite (CAS 110-46-3, 1.57 mL, 11.65 mmol, 1.5 equiv) was added, and the reaction mixture was stirred at RT for 30 minutes. 4-Amino-3-isopropyl-1-m-tolyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid ethyl ester (2.63 g, 7.77 mmol, 1.0 equiv) was added. The reaction mixture was stirred at 75° C. for 2.5 h. The reaction mixture was cooled down to 0° C., and the resulting suspension was filtered. The solid was washed with cold acetonitrile and dried in vacuo to afford the titled compound. The filtrate was concentrated in vacuo and purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate gradient from 100/0 to 98/2) to provide additional titled compound.

Method H1′: Alternative Conditions for Chlorination Route 1 Step 9

To the 4-amino intermediate (1 equiv) in acetonitrile at RT is added isopentylnitrite (CAS 110-46-3, from 3 to 6 eq) followed by copper(I) chloride (CAS 7758-89-6, from 3 to 6 equiv), and the reaction mixture is stirred at RT for 1 h to 24 h. The reaction mixture is diluted with dichloromethane and with a saturated solution of sodium hydrogencarbonate. The two phases are separated, and the aqueous phase is extracted with dichloromethane. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue is purified by flash chromatography on silica gel to afford the titled compound.

Illustrative synthesis of HP03: ethyl 4-chloro-1-[3-(dimethylamino)phenyl]-3-isopropyl-pyrazolo[3,4-b]pyridine-6-carboxylate

To 4-amino-1-(3-dimethylamino-phenyl)-3-isopropyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid ethyl ester (1 g, 2.74 mmol, 1 equiv) in acetonitrile (10 mL) at RT was added isopentylnitrite (CAS 110-46-3, 1.1 mL, 8.21 mmol, 3 equiv) followed by copper(I) chloride (CAS 7758-89-6, 0.82 g, 8.21 mmol, 3 equiv), and the reaction mixture was stirred at RT for 1 h. The reaction mixture was diluted with dichloromethane and with a saturated solution of sodium hydrogencarbonate. The two phases were separated, and the aqueous phase was extracted with dichloromethane. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue was purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate gradient from 100/0 to 90/10) to afford the titled compound.

Synthesis of HP13: ethyl 4-chloro-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

Step 1: 6-Hydroxy-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid ethyl ester

5-Amino-3-methyl-1-phenylpyrazole (CAS: 1131-18-6, 6.83 g, 39.4 mmol) was dissolved in AcOH (70 mL). Diethyloxalacetate sodium salt (CAS: 40876-98-0, 9.12 g, 44.4 mmol, 1.1 equiv) was added, and the reaction mixture was refluxed until complete conversion. The reaction mixture was concentrated in vacuo, and the residue was taken up in cyclohexane (2×100 mL) and concentrated in vacuo again. The residue was suspended in a mixture of MeOH/water (150 mL/100 mL). The resulting precipitate was collected by filtration and washed with heptane. The solid was dried under vacuum to provide the titled compound.

Step 2: 6-Bromo-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid ethyl ester

6-Hydroxy-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid ethyl ester (7.27 g, 24.5 mmol) was solubilized in anisole (30 mL). Phosphorous(V) oxybromide (CAS 7789-59-5, 8.23 g, 29.3 mmol, 1.2 equiv) was added, and the reaction mixture was refluxed at 140° C. for 1 h. The reaction mixture was cooled down to room temperature and basified with a saturated solution of sodium hydrogencarbonate. The reaction mixture was extracted twice with ethyl acetate, and the combined organic phases were washed with brine, dried over Na₂SO₄, filtered and concentrated in vacuo. The residue was purified by filtration on a pad of silica gel (200 g), heptane/EtOAc 100/0 to 90/10) to give the titled compound.

Step 3: 6-Bromo-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid

6-Bromo-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid ethyl ester (3.90 g, 10.8 mmol) was suspended in ethanol (20 mL). An aqueous solution of 1 M sodium hydroxide (20 mL, 20 mmol, 1.9 equiv) was added, and the reaction mixture was stirred at 70° C. for 30 min. The reaction mixture was then concentrated in vacuo. The residue was acidified with an aqueous solution of 2 M HCl and extracted with ethyl acetate. The organic phase was dried over Na₂SO₄, filtered and concentrated in vacuo to yield the titled compound.

Step 4: (6-Bromo-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridin-4-yl)-carbamic acid tert-butyl ester

6-Bromo-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid (3.50 g, 10.4 mmol) was suspended in toluene (35 mL). tert-Butanol (2 mL, 21.6 mmol, 2.1 equiv), triethylamine (4.4 mL, 31.2 mmol, 3.0 equiv) and diphenylphosphoryl azide (CAS 26386-88-9, 3.2 mL, 14.8 mmol, 1.4 equiv) were successively added. The reaction mixture was refluxed for 1.5 h. The reaction mixture was cooled down to RT and concentrated in vacuo, then partitioned between ethyl acetate and water. The aqueous phase was further extracted with ethyl acetate. The combined organic phases were washed with brine, dried over Na₂SO₄, filtered and concentrated in vacuo. The residue was purified by filtration on a pad of silica gel (200 g, heptane/EtOAc 100/0 to 90/10) to give the titled compound.

Step 5: (6-Cyano-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridin-4-yl)-carbamic acid tert-butyl ester

(6-Bromo-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridin-4-yl)-carbamic acid tert-butyl ester (4.16 g, 10.3 mmol) was solubilized in dry dimethylformamide (20 mL) in a sealed vial. Zinc cyanide (CAS 557-21-1, 0.727 g, 6.2 mmol, 0.6 equiv) was added, and the reaction mixture was degassed with argon for 5 minutes. Tetrakis(triphenylphosphine)palladium(O) (CAS 14221-01-3, 0.595 g, 0.5 mmol, 0.05 equiv) was added, and the vial was sealed. The reaction mixture was stirred at 100° C. for 1 hour. The reaction was not complete. Additional tetrakis(triphenylphosphine)palladium(O) (CAS 14221-01-3, 0.595 g, 0.5 mmol, 0.05 equiv) and zinc cyanide (CAS 14221-01-3, 0.485 g, 4.1 mmol, 0.4 equiv) were added at RT, and the vial was sealed again. The reaction mixture was stirred at 100° C. for one hour and cooled down to room temperature. Water was added to the reaction mixture and precipitation occurred. The suspension was filtered, and the cake was washed with water. The solid residue was taken up with dichloromethane and with an aqueous solution of 0.5 M NaOH. The organic phase was separated, dried over Na₂SO₄, filtered and concentrated. The residue was purified by filtration on a pad of silica gel (150 g, heptane/EtOAc 100/0 to 60/40) to give the titled compound mixed with (6-cyano-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridin-4-yl)-carbonitrile. The mixture was engaged in the next step without further purification.

Step 6: 4-Amino-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid hydrochloride salt

A mixture of (6-cyano-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridin-4-yl)-carbamic acid tert-butyl ester and (6-cyano-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridin-4-yl)-carbonitrile (3.5 g) was suspended in 6 M HCl (50 mL). The reaction mixture was refluxed for 18 h. The reaction mixture was cooled to 0° C. and the obtained suspension was filtered. The solid was washed with an aqueous solution of 0.1 M HCl. The filtrate was concentrated in vacuo and precipitation occurred. The solid was also collected by filtration. The combined solids were dried in vacuo to yield the titled compound.

Step 7: 4-Amino-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid ethyl ester

4-Amino-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid hydrochloride salt (2.03 g, 7.6 mmol) was solubilized in ethanol (40 mL). Thionyl chloride (CAS 7719-09-7, 1.16 mL, 15.9 mmol, 2.1 equiv) was carefully added. The reaction mixture was refluxed for 24 hours. The reaction mixture was concentrated in vacuo and partitioned between ethyl acetate and aqueous saturated NaHCO₃. The aqueous phase was further extracted with ethyl acetate. The combined organic phases were dried over Na₂SO₄, filtered and concentrated in vacuo to give the titled compound.

Step 8: 4-Chloro-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid ethyl ester

Copper(II) chloride (CAS 7447-39-4, 0.908 g, 6.75 mmol, 1.0 equiv) was added to acetonitrile (50 mL). Isopentylnitrite (CAS 110-46-3, 1.4 mL, 10.1 mmol, 1.5 equiv) was added, and the reaction mixture was stirred at 75° C. for 5 minutes. 4-Amino-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid ethyl ester (2.0 g, 6.75 mmol, 1.0 equiv) dissolved in acetonitrile (50 mL) was added. The reaction mixture was stirred at 75° C. for 2.5 h. The reaction mixture was cooled down and concentrated in vacuo. Water was added to the residue, and the mixture was extracted with ethyl acetate. Copper salts prevented clean extraction. The suspension was filtered through diatomaceous earth. The organic phase was dried over Na₂SO₄, filtered and concentrated. The residue was suspended in ethanol (10 mL) and filtered. The solid was dried in vacuo to give the titled compound. The copper salts on the diatomaceous earth were washed with dichloromethane. The filtrate was concentrated to provide additional titled compound.

Method H2: Synthesis of Halogenated Pyrazolopyridine (Route 2) Illustrative synthesis of HP02: methyl 4-chloro-3-cyclobutyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

Step 1: 3-cyclobutyl-1-phenyl-pyrazolo[3,4-b]pyridine-4,6-diol

To a mixture of 3-cyclobutyl-1-phenyl-1H-pyrazol-5-amine (AMP29, 74.0 g, 347 mmol) in oxydibenzene (450.0 g, 2.64 mol) was added diethyl malonate (CAS 105-53-3, 139.0 g, 867 mmol). The system was heated at 130-150° C. for 40 h. By this time solid had precipitated and heating was stopped. Two more reactions were set up as described above. All three reaction mixtures were combined. The combined mixture was cooled to below 40° C. and diluted with about 1.8 L of diethyl ether, and the resulting suspension was stirred for 2 h and then filtered. The collected solids were rinsed with diethyl ether (1 L). The solids were dried on the filter to give the titled compound. ¹H NMR (400 MHz, DMSO-d6) δ ppm 11.28 (s, 1H), 8.18 (d, J=7.9 Hz, 2H), 7.58-7.39 (m, 2H), 7.21 (t, J=7.1 Hz, 1H), 5.85 (s, 1H), 3.88 (quin, J=8.4 Hz, 1H), 2.44-2.22 (m, 4H), 2.07-1.78 (m, 2H).

Step 2: 4,6-dichloro-3-cyclobutyl-1-phenyl-pyrazolo[3,4-b]pyridine

A mixture of 3-cyclobutyl-1-phenyl-pyrazolo[3,4-b]pyridine-4,6-diol (60.0 g, 213 mmol) in phenyl dichlorophosphate (CAS 770-12-7,135 g, 640 mmol) was stirred at 170° C. for 15 h. Two more reactions were set up as described above. All three reaction mixtures were combined and poured into ice water (5 L) keeping the internal temperature <10° C. The mixture was neutralized with concentrated NH₄OH (500 mL) to pH 6-7, then the suspension was stirred for 2 h. As the pH increased and with continued stirring, the semi-solid suspension becomes a flowing solid. The solid was collected by filtration. The wet solid was dissolved in dichloromethane (3 L) and filtered through a short path of silica gel (2 kg), eluting with dichloromethane (15 L). The filtrate was concentrated to a solid which was triturated with acetonitrile (1.5 L) and collected by filtration to give the titled compound. ¹H NMR (400 MHz, DMSO-d6) δ ppm 8.20 (d, J=7.9 Hz, 2H), 7.51 (t, J=7.5 Hz, 2H), 7.35-7.27 (m, 1H), 7.16 (s, 1H), 4.15 (quin, J=8.4 Hz, 1H), 2.63-2.41 (m, 4H), 2.20-2.07 (m, 1H), 2.00 (s, 1H).

Step 3: methyl 4-chloro-3-cyclobutyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

To a mixture of 4,6-dichloro-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine (50.0 g, 157 mmol) in methanol (700 mL) was added triethylamine (31.8 g, 314 mmol) and Pd(dppf)Cl₂.DCM (CAS 95464-05-4, 6.4 g, 7.86 mmol). The system was heated at 60° C. under CO (30 psi) for 40 h. Two more reactions were set up as described above. All three reaction mixtures were combined and concentrated to give a semisolid which was dissolved in dichloromethane (3 L) and filtered through a 2 kg plug of silica gel. After concentration, about 130 g of solid was obtained. This solid was taken up in 1.3 L of ethyl acetate with heating. This solution was stirred at room temperature. Solids came out over a couple of minutes, and then 1.3 L of hexane was added in a thin stream via addition funnel with stirring for 2 hours. The solids were collected by filtration to give the titled compound. ¹H NMR (400 MHz, CDCl3) δ ppm 8.38-8.27 (m, 2H), 7.95 (s, 1H), 7.53 (t, J=7.9 Hz, 2H), 7.35-7.27 (m, 1H), 4.21 (q, J=8.6 Hz, 1H), 4.08-4.03 (m, 1H), 2.66-2.40 (m, 4H), 2.22-1.93 (m, 2H).

Illustrative synthesis of HP17: 4-chloro-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Step 1: 4-hydroxy-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridin-6(7H)-one

A solution of 5-amino-3-methyl-1-phenylpyrazole (CAS 1131-18-6, 6 g, 34.6 mmol) and diethyl malonate (5.28 mL, 34.6 mmol) in diphenyl ether (25 mL) was heated at reflux for 22 hours. Solids gradually precipitated from the reaction mixture. The reaction mixture was cooled to RT, diluted with diethyl ether (50 mL), and stirred at RT for 1 h. The solid was collected by filtration, washed with diethyl ether (25 mL), and dried in a vacuum oven at 50° C. for 16 hours. The filtrate was concentrated in vacuo to remove diethyl ether, and the resulting solution (of some unreacted starting material) in diphenyl ether solution was heated to reflux for 2 hours. Then the reaction mixture was cooled to RT, diluted with diethyl ether (25 mL) and filtered to give additional solid product. The filter cake was washed with diethyl ether (2×25 mL), air dried, and combined with first lot of solid, and this was dried under vacuum to give a total of 4.25 g of the titled compound (51% yield). ¹H NMR (501 MHz, DMSO-d₆) δ ppm 2.50 (s, 3H), 5.86 (s, 1H), 7.21 (tt, J=7.4, 1.2 Hz, 1H), 7.39-7.49 (m, 2H), 8.11-8.23 (m, 2H), 10.88 (s, 1H), 11.32 (s, 1H).

Step 2: 3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4,6-diylbis(trifluoromethanesulfonate)

To a cold (<0° C.) suspension of 4-hydroxy-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridin-6(7H)-one (4.25 g, 17.62 mmol) in acetonitrile (100 mL) was added pyridine (3.56 mL, 44.0 mmol) and trifluoromethanesulfonic anhydride (5.21 mL, 30.8 mmol) in a dropwise manner. The cooling bath was removed, and the reaction mixture stirred at RT for 2 hours. The reaction mixture was then diluted with water (100 mL) and stirred for 5 min. The resulting precipitates were collected by filtration, washed with water and dried in a vacuum oven at 50° C. for 16 h to give 8.0 gm of the titled compound (90% Yield). ¹H NMR (400 MHz, CDCl₃) δ ppm 2.78 (s, 3H), 7.03 (s, 1H), 7.35-7.42 (m, 1H), 7.50-7.58 (m, 2H), 8.08-8.15 (m, 2H).

Step 3: 4,6-dichloro-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine

A mixture of 3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4,6-diyl bis(trifluoromethanesulfonate) (8.00 g, 15.83 mmol) and 4.0 N hydrochloric acid in dioxane (39.6 mL, 158 mmol) was stirred in a sealed tube at 120° C. for 6 hours. The reaction mixture was concentrated in vacuo and purified by flash chromatography using a 120 g silica gel cartridge, eluting with 0-3.5% MTBE/heptanes to afford 3.41 g of the titled compound (78% yield). Note that the reaction can also be run at 100° C. for 16 hours instead of 120° C. ¹H NMR (400 MHz, CDCl₃) δ ppm 2.81 (s, 3H), 7.21 (s, 1H), 7.31-7.38 (m, 1H), 7.54 (t, 2H), 8.17 (d, 2H).

Step 4: methyl 4-chloro-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

To a 250 mL stainless steel pressure bottle was added 4,6-dichloro-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine (3.4063 g, 12.25 mmol), Pd-dppf (Heraeus) (0.179 g, 0.245 mmol), MeOH (70 mL), and triethylamine (3.41 mL, 24.49 mmol). The pressure bottle reactor was degassed with argon several times, followed by addition of carbon monoxide, and the reaction was heated to 100° C. for 30 minutes, maintaining the reaction under 60 psi pressure of carbon monoxide. The reaction mixture was concentrated in vacuo and purified by flash chromatography using a 120 g silica gel cartridge, eluting with 100% DCM to obtain 3.09 g of the titled compound (84% yield). Note that lowering the reaction temperature from 100° C. to 50° C., and increasing the reaction time from 30 minutes to 2 hours, also gives desired product. ¹H NMR (400 MHz, CDCl₃) δ ppm 2.86 (s, 3H), 4.05 (s, 3H), 7.29-7.37 (m, 1H), 7.49-7.60 (m, 2H), 7.98 (s, 1H), 8.24-8.32 (m, 2H).

Step 5: 4-chloro-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

To a solution of methyl 4-chloro-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (3.09 g, 10.24 mmol) in tetrahydrofuran (76 mL) was added potassium trimethylsilanolate (1.577 g, 12.29 mmol), and the resulting suspension was stirred at 50° C. for 1 hour. The reaction mixture was acidified with concentrated aqueous HCl to pH 1, and the mixture was partitioned between MTBE and water. The organic extract were washed with brine, dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to obtain 2.90 g of the titled compound (99% yield). ¹H NMR (400 MHz, DMSO-d₆) δ ppm 2.71 (s, 3H), 7.30-7.37 (m, 1H), 7.50-7.59 (m, 2H), 7.87 (s, 1H), 8.16-8.23 (m, 2H), 13.75 (s, 1H).

Illustrative synthesis of HP19: Methyl 4-chloro-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Step 1: 3-Cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-4,6-diol

A mixture of 3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazol-5-amine (AMP93, 5 g, 18.6 mmol) and diethyl malonate ([105-53-3], 8.5 mL, 55.8 mmol) was heated at 100° C. for 30 minutes and then at 170° C. for 3 hours. The reaction mixture was cooled down to RT and dissolved in dichloromethane (60 mL). The resultant solution was poured into a stirred solution of n-heptane (700 mL). The precipitate was collected by filtration, washed with n-heptane and dried at 40° C. under reduced pressure to give the titled compound.

Step 2: 4,6-Dichloro-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine

A three-neck round-bottom flask equipped with a Dean-Stark apparatus was charged with phenyl dichlorophosphate ([770-12-7], 854 g, 4.05 mol). 3-Cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-4,6-diol (404 g, 1.35 mol) was added in portions over a period of 5 minutes. The temperature was increased to 170° C. over a period of 1 hour, and the stirring at 170° C. was continued for 21 hours. The reaction mixture was cooled down to 50° C. and added slowly to a stirred aqueous 4 N NaOH (5 L) keeping the temperature below 20° C. The suspension was stirred for 1 hour at 10-15° C., and then cold water (3 L) was added. The precipitate was collected by filtration, washed with water and dried at 40° C. under reduced pressure to give the titled compound.

Step 3: methyl 4-chloro-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

A pressured vessel was charged with 4,6-dichloro-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine (5 g, 14.9 mmol), Pd(dppf)Cl₂.DCM (CAS 95464-05-4, 218 mg, 0.3 mmol), and sodium acetate (1.8 g, 22.3 mmol) in dioxane/methanol (1:1, 25 mL). The system was loaded with CO (4 bars) and heated at 40° C. for 2 hours. The vessel was cooled to RT, and the conversion was monitored by LCMS. The reaction vessel was charged again with CO (4 bars) and heated at 40° C. The sequence was repeated until full conversion was observed. The crude mixture was concentrated under reduced pressure and purified by flash column chromatography eluting with a mixture of n-heptane/dichloromethane (90/10 to 30/70) to give the titled compound.

Method H3: Synthesis of Halogenated Pyrazolopyridine (Route 3)

Step 1: Diethyl but-2-enedioate

To a suspension of aminopyrazole (1 equiv) in ethanol (150 mL) is added diethyl acetylenedicarboxylate (1.1 equiv). The reaction mixture is stirred at room temperature for 4 hours. The reaction mixture is concentrated. The crude residue is purified by silica gel column chromatography (heptane/EtOAc 100/0 to 70/30) to give the titled compound.

Step 2: Pyrazolopyridine formation

The diethyl but-2-enedioate is heated under air atmosphere at 190-195° C. for one hour. The reaction mixture is cooled to room temperature and is partitioned between dichloromethane and water. The aqueous phase is separated and extracted two times with dichloromethane. The combined organic phases were dried, filtered and concentrated in vacuo. The crude residue can be purified by silica gel column chromatography to provide the pyrazolopyridine.

Step 3: Chlorination

A solution of the above pyrazolopyridine (1 equiv) in phosphorus(V) oxychloride (32 equiv) was stirred at 115° C. for 1 h. The reaction mixture is then cooled to room temperature and concentrated in vacuo. The residue is dissolved in ethyl acetate, and the reaction mixture is added dropwise to a solution of saturated of sodium hydrogencarbonate till total neutralization of phosphorus(V) oxychloride (pH 8). The aqueous phase is separated and extracted two times with ethyl acetate. The combined organic phases are washed with brine, dried, filtered and concentrated in vacuo. The crude residue can be purified by silica gel column chromatography to provide the chlorinated pyrazolopyridine from which the dimethoxybenzyl group has also been removed.

Illustrative synthesis of HP08: 4-Chloro-3-isopropyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid ethyl ester

Step 1: 2-[2-(2,4-Dimethoxy-benzyl)-5-isopropyl-2H-pyrazol-3-ylamino]-but-2-enedioic acid diethyl ester

To a suspension of 2-(2,4-dimethoxy-benzyl)-5-isopropyl-2H-pyrazol-3-ylamine (AMP28, 18.14 g, 65.88 mmol) in ethanol (150 mL) was added diethyl acetylenedicarboxylate (CAS: 762-21-0, 11.60 mL, 72.47 mmol). The reaction mixture was stirred at room temperature for 4 hours. The reaction mixture was concentrated. The crude residue was purified by silica gel column chromatography (heptane/EtOAc 100/0 to 70/30) to give the titled compound.

Step 2: Compound HP06: 1-(2,4-Dimethoxy-benzyl)-4-hydroxy-3-isopropyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid ethyl ester

2-[2-(2,4-Dimethoxy-benzyl)-5-isopropyl-2H-pyrazol-3-ylamino]-but-2-enedioic acid diethyl ester (13.46 g, 30.21 mmol) was heated under air atmosphere at 190-195° C. for one hour. The reaction mixture cooled to room temperature and was partitioned between dichloromethane and water. The aqueous phase was separated and extracted two times with dichloromethane. The combined organic phases were dried over MgSO₄, filtered and concentrated in vacuo. The crude residue was purified by silica gel column chromatography (heptane/EtOAc 100/0 to 60/40) to provide the titled compound.

Step 3: Compound HP08: 4-Chloro-3-isopropyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid ethyl ester

A solution of 1-(2,4-dimethoxy-benzyl)-4-hydroxy-3-isopropyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid ethyl ester (HP06, 4.02 g, 10.06 mmol) in phosphorus(V) oxychloride (CAS 100025-87-3, 30 mL, 322 mmol) was stirred at 115° C. for 1 h. The reaction mixture was then cooled to room temperature and concentrated in vacuo. The residue was dissolved in ethyl acetate, and the reaction mixture was added dropwise to a solution of saturated of sodium hydrogencarbonate till total neutralization of phosphorus(V) oxychloride (pH 8). The aqueous phase was separated and extracted two times with ethyl acetate. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The crude residue was purified by silica gel column chromatography (heptane/EtOAc 100/0 to 75/25) to provide the titled compound.

Illustrative Synthesis of HP20: ethyl 1-tert-butyl-3-cyclobutyl-4-[(trifluoromethanesulfonyl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Step 1: diethyl 2-[(1-tert-butyl-3-cyclobutyl-1H-pyrazol-5-yl)amino]but-2-enedioate

In an amber round bottom flask, diethyl acetylenedicarboxylate ([762-21-0], 14.8 mL, 87 mmol) was added to a suspension of AMP94 (15.2 g, 78.8 mmol) in ethanol (200 mL). The reaction mixture was stirred at room temperature for 20 hours, and the mixture was concentrated in vacuo. The crude residue was purified by silica gel column chromatography (heptane/dichloromethane 100/0 to 0/100) to give the titled compound.

Step 2: ethyl 1-tert-butyl-3-cyclobutyl-4-hydroxy-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

In a sealed tube, a suspension of diethyl 2-[(1-tert-butyl-3-cyclobutyl-1H-pyrazol-5-yl)amino]but-2-enedioate (5 g, 13.8 mmol) in Dowtherm® A (5 mL) was heated at 185-190° C. for 24 hours. The reaction mixture was cooled to room temperature and was partitioned between n-heptane and acetonitrile. The acetonitrile phase was separated and evaporated under reduced pressure. The crude sample was purified by silica gel column chromatography (dichloromethane/n-heptane) to give the titled compound.

Step 3: ethyl 1-tert-butyl-3-cyclobutyl-4-[(trifluoromethanesulfonyl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Trifluoromethanesulfonic anhydride ([358-23-6], 1.9 mL, 11.3 mmol) was added dropwise to a solution of ethyl 1-tert-butyl-3-cyclobutyl-4-hydroxy-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (2.5 g, 7.89 mmol) and pyridine (1.9 mL, 23.5 mmol) in acetonitrile (80 mL), maintaining the temperature around 20-25° C. The reaction mixture was stirred at RT for 20 hours. Then solid sodium hydrogencarbonate and few milliliters of water were added, and the reaction mixture was concentrated in vacuo. The residue was taken up in dichloromethane and water. The two phases were separated, and the aqueous phase was again extracted with dichloromethane. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated under reduced pressure. The resulting residue was purified by silica gel chromatography (n-heptane/ethyl acetate) to yield the titled compound.

Synthesis of HP12: methyl 4-chloro-1-cyclohexyl-3-isopropyl-pyrazolo[3,4-b]pyridine-6-carboxylate

Step 1: 1-cyclohexyl-3-isopropyl-pyrazolo[3,4-b]pyridine-4,6-diol

A mixture of AMP23 (5.0 g, 24.1 mmol) and diethylmalonate (CAS 105-53, 37.36 mL, 48.2 mmol, 2.0 equiv) was stirred at 190° C. for 2 hours. The reaction mixture was then cooled to RT, and diethyl ether was added. The obtained suspension was filtered; the solid was washed with pentane and dried in vacuo to give the titled compound.

Step 2: [1-cyclohexyl-3-isopropyl-6-(trifluoromethylsulfonyloxy)pyrazolo[3,4-b]pyridin-4-yl]trifluoromethanesulfonate

Trifluoromethanesulfonic anhydride (CAS 358-23-6, 6.26 mL, 37.2 mmol, 1.75 equiv) was added dropwise at 0° C. to a solution of 1-cyclohexyl-3-isopropyl-pyrazolo[3,4-b]pyridine-4,6-diol (5.85 g, 21.2 mmol) and pyridine (4.3 mL, 53.1 mmol, 2.5 equiv) in acetonitrile (145 mL). The reaction mixture was stirred at RT for 16 hours. Dichloromethane and water were added to the reaction mixture. The two phases were separated, and the organic phase was washed with water and brine, dried over MgSO₄, filtered and concentrated in vacuo. The residue was taken up in toluene and concentrated again in vacuo to give the titled compound.

Step 3: 4,6-dichloro-1-cyclohexyl-3-isopropyl-pyrazolo[3,4-b]pyridine

A mixture of [1-cyclohexyl-3-isopropyl-6-(trifluoromethylsulfonyloxy)pyrazolo[3,4-b]pyridin-4-yl]trifluoromethanesulfonate (10.86 g, 20.1 mmol) and 4 N HCl in dioxane (50 mL, 200 mmol, 10 equiv) was stirred at 100° C. for 16 hours in a sealed tube. The reaction mixture was cooled to RT and concentrated in vacuo. The residue was purified by chromatography on silica gel (heptane/dichloromethane 100/0 to 80/20) to yield the titled compound.

Step 4: HP12: methyl 4-chloro-1-cyclohexyl-3-isopropyl-pyrazolo[3,4-b]pyridine-6-carboxylate

Triethylamine (1.9 mL, 13.6 mmol, 2.0 equiv) and Pd(dppf)Cl₂ (CAS: 72287-26-4, 100 mg, 0.14 mmol, 0.02 equiv) were added to a solution of 4,6-dichloro-1-cyclohexyl-3-isopropyl-pyrazolo[3,4-b]pyridine (2.13 g, 6.82 mmol) in methanol (55 mL). The system was filled at RT with CO (40 psi) and heated at 100° C. for 1 hour. The reaction mixture was cooled down to RT and concentrated in vacuo. The residue was purified by chromatography on silica gel (heptane/ethyl acetate 100/0 to 90/10) to yield the titled compound.

Synthesis of HP14: ethyl 3-cyclobutyl-1-[(2,4-dimethoxyphenyl)methyl]-4-(trifluoromethylsulfonyloxy)pyrazolo[3,4-b]pyridine-6-carboxylate

Trifluoromethanesulfonic anhydride (CAS 358-23-6, 92 μL, 0.56 mmol, 1.45 equiv) was added dropwise at RT to a solution of HP15 (160 mg, 0.39 mmol, 1 equiv) and pyridine (46 μL, 0.58 mmol, 1.5 equiv) in acetonitrile (4 mL). The reaction mixture was stirred at RT for 3 h. Then solid sodium hydrogencarbonate and few milliliters of water were added, and the reaction mixture was concentrated in vacuo. The residue was taken up in dichloromethane and water. The two phases were separated, and the aqueous phase was extracted with dichloromethane. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue was purified by flash chromatography on silica gel (eluent system: heptane/dichloromethane gradient from 100/0 to 0/100) to yield the titled compound.

Synthesis of HP18: 4-chloro-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carbonitrile

Step 1: 6-Hydroxy-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid ethyl ester

5-Amino-3-methyl-1-phenylpyrazole (CAS: 1131-18-6, 6.83 g, 39.4 mmol) was dissolved in AcOH (70 mL). Diethyloxalacetate sodium salt (CAS: 40876-98-0, 9.12 g, 44.4 mmol, 1.1 equiv) was added, and the reaction mixture was refluxed till the conversion (followed by LCMS) was total. The reaction mixture was concentrated, and the residue was taken up in cyclohexane (2×100 mL) and concentrated. The residue was triturated in MeOH/water (150 mL/100 mL). The resulting precipitate was collected by filtration and washed with heptane. The solid was dried to provide the titled compound.

Step 2: 6-Bromo-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid ethyl ester

6-Hydroxy-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid ethyl ester (7.27 g, 24.5 mmol) was solubilized in anisole (30 mL). Phosphorous(V) oxybromide (8.23 g, 29.3 mmol, 1.2 equiv) was added, and the reaction mixture was refluxed at 140° C. for 1 h. The reaction mixture was cooled to room temperature and saturated NaHCO₃ was added. The reaction mixture was extracted twice with ethyl acetate, and the combined organic phases were washed with brine, dried over Na₂SO₄, filtered and concentrated. The residue was purified by filtration on a pad of silica gel (200 g), heptane/EtOAc 100/0 to 90/10) to give the titled compound.

Step 3: 6-Bromo-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid

6-Bromo-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid ethyl ester (3.90 g, 10.8 mmol) was suspended in ethanol (20 mL). 1 M NaOH (20 mL, 20 mmol, 1.9 equiv) was added, and the reaction mixture was stirred at 70° C. for 30 min. The reaction mixture was then concentrated. The residue was acidified with 2 M HCl and extracted with ethyl acetate. The organic phase was dried over Na₂SO₄, filtered and concentrated yielding the titled compound.

Step 4: 6-bromo-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridin-4-amine

6-Bromo-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid (3.50 g, 10.4 mmol) was suspended in toluene (35 mL). tert-Butanol (2 mL, 21.6 mmol, 2.1 equiv), triethylamine (4.4 mL, 31.2 mmol, 3.0 equiv) and diphenylphosphoryl azide (3.2 mL, 14.8 mmol, 1.4 equiv) were successively added. The reaction mixture was refluxed for 1.5 h. The reaction mixture was concentrated and then partitioned between ethyl acetate and water. The aqueous phase was further extracted with ethyl acetate. The combined organic phases were washed with brine, dried over Na₂SO₄, filtered and concentrated. The residue was purified on a silica cake (200 g, heptane/EtOAc 100/0 to 90/10) to give the titled compound.

Step 5: 6-bromo-4-chloro-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine

Copper(II) chloride (28 mg, 0.21 mmol) and isopentylnitrite (71 μL, 0.53 mmol) in acetonitrile (4 mL) were heated at 70° C. for 5 minutes. The compound from Step 4 (107 mg, 0.35 mmol) was solubilized in acetonitrile (4 mL) and added to the previous solution. The heating at 70° C. was continued and copper (II) chloride (28 mg, 0.21 mmol) was added two times every hour. After 2.5 hours, the reaction mixture was left cooling to RT, and the mixture was concentrated under reduced pressure. Water was added, and the aqueous phase was extracted with ethyl acetate. The organic phase was washed with brine, dried over sodium sulfate and concentrated under reduced pressure. The residue was purified by flash column chromatography eluting with n-heptane/ethyl acetate to give the titled compound.

Step 6: 4-chloro-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carbonitrile

The compound from Step 5 (192 mg, 0.6 mmol) was solubilized in dry dimethylformamide (1 mL) in a vial. Zinc cyanide (35 mg, 0.3 mmol) was added, and the reaction mixture was degassed with argon for 5 minutes.

Tetrakis(triphenylphosphine)palladium(O) (70 mg, 0.06 mmol) was added, and the vial was sealed. The reaction mixture was stirred at 100° C. for 0.5 hour. The reaction mixture was cooled to room temperature, and the crude mixture was partitioned between a saturated aqueous solution of NaHCO₃ and ethyl acetate. The organic phase was washed with a saturated aqueous solution of NaCl, dried over sodium sulfate, filtered and concentrated in vacuo. The residue was purified by flash column chromatography eluting with n-heptane/ethyl acetate to give the titled compound.

Synthesis of intermediate HP21: 1-(4-fluorophenyl)-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-4, 6-diol

In a sealed tube, a suspension of AMP96 (215 mg, 0.91 mmol) and diethyl malonate ([105-53-3], 418 μL, 2.75 mmol) in Dowtherm® A was heated at 200° C. 4 hours. The reaction mixture was cooled down to 70-80° C. and poured into stirred n-heptane (200 mL). The resultant precipitate was collected by filtration, washed with n-heptane and dried at 40° C. under reduced pressure to give the titled compound.

Synthesis of intermediate HP22: 1-(4-fluorophenyl)-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-4,6-diyl bis(trifluoromethanesulfonate)

Trifluoromethanesulfonic anhydride ([358-23-6], 302 μL, 1.8 mmol) was added dropwise to a solution of HP21 (270 mg, 0.9 mmol) and pyridine (220 μL, 2.25 mmol) in acetonitrile (5 mL), maintaining the temperature around 20-25° C. The reaction mixture was stirred at RT for 20 hours. The reaction was diluted with DCM and extracted twice with a saturated aqueous solution of NaHCO₃. The organic phase was separated, dried over MgSO₄, filtered and concentrated under reduced pressure. The resulting residue was purified by silica gel chromatography (n-heptane/ethyl acetate) to yield the titled compound.

Synthesis of HP25: methyl 4-chloro-3-cyclobutyl-1-cyclohexyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Step 1: 3-cyclobutyl-1-cyclohexyl-4-hydroxy-3aH-pyrazolo[3,4-b]pyridin-6-one

A mixture of 5-cyclobutyl-2-cyclohexyl-2H-pyrazol-3-ylamine (AMP35, 10 g, 45.7 mmol) and diethyl malonate ([105-53-3], 27.7 mL, 183 mmol) in diphenylether (50 mL) was heated at 130° C. over approximately 60 hours. The reaction mixture was cooled down to RT and quenched with 0.5 M NaOH solution (100 mL, 50 mmol). Extraction with EtOAc gave an aqueous phase that was acidified with a 12 M HCl solution (4.3 mL, 51.6 mmol) giving rise to a suspension. This suspension was extracted with EtOAc. The obtained organic layer was dried and concentrated to give the titled compound that was used as such.

Step 2: 4,6-dichloro-3-cyclobutyl-1-cyclohexyl-pyrazolo[3,4-b]pyridine

The 3-cyclobutyl-1-cyclohexyl-4-hydroxy-3aH-pyrazolo[3,4-b]pyridin-6-one (5.15 g, 17.9 mmol) was suspended in phenyl dichlorophosphate ([770-12-7], 8.01 mL, 53.8 mmol). The mixture was heated at 130° C. overnight. Next, the mixture was diluted in DCM and poured into ice water. After increasing the pH till 7-8 with a saturated NH₄OH solution, the biphasic mixture was stirred for 30 minutes. Subsequently, the organic phase was separated, dried and concentrated to give a residue. This residue was purified by chromatography using a petroleum ether/EtOAc gradient (100/0 to 90/10). This resulted in the titled compound that was used as such.

Step 3: methyl 4-chloro-3-cyclobutyl-1-cyclohexyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

In a Parr apparatus, 4,6-dichloro-3-cyclobutyl-1-cyclohexyl-pyrazolo[3,4-b]pyridine (2.17 g, 6.72 mmol) was dissolved in MeOH (50 mL) together with Pd(dppf)Cl₂.DCM (CAS 95464-05-4, 275 mg, 0.33 mmol) and triethylamine (1.87 mL, 13.4 mmol). The system was loaded with CO (5 bar) and heated at 45° C. for 18 hours. After cooling down the mixture till RT, the mixture was concentrated, and the obtained residue was purified by chromatography using a petroleum ether/EtOAc gradient (100/0 till 95/5). This yielded the titled compound.

Illustrative synthesis of HP27: 4-chloro-1-(4-fluorophenyl)-5-methyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Step 1: 1-(4-fluorophenyl)-4-hydroxy-5-methyl-3-(propan-2-yl)-1,7-dihydro-6H-pyrazolo[3,4-b]pyridin-6-one

To a flask containing 2-(4-fluoro-phenyl)-5-isopropyl-2H-pyrazol-3-ylamine (8.0 g, 36.5 mmol, AMP13) in oxydibenzene (62.1 g, 365 mmol) was added diethyl 2-methylmalonate (4.0 g, 22.96 mmol). The reaction mixture was heated at 130° C. for 20 hours and then at 150° C. for 35 hours before being returned to room temperature. Heptane was added (180 mL), and the suspension was stirred at room temperature overnight. The solids were collected by filtration, washed with heptane (30 mL), and dried to give the titled compound. ¹H NMR (400 MHz, CD₃OD) δ ppm 7.80-7.75 (m, 2H), 7.26-7.20 (m, 2H), 3.50 (hept, J=7.0 Hz, 1H), 2.05 (s, 3H), 1.40 (d, J=7.0 Hz, 6H); MS (DCI) m/z 302 (M+H)⁺.

Step 2: 4,6-dichloro-1-(4-fluorophenyl)-5-methyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine

To a flask containing 1-(4-fluorophenyl)-4-hydroxy-5-methyl-3-(propan-2-yl)-1,7-dihydro-6H-pyrazolo[3,4-b]pyridin-6-one (4.5 g, 14.93 mmol) under nitrogen was added phenyl phosphorodichloridate (6.30 g, 29.9 mmol). The reaction mixture was heated to 180° C. and stirred for five hours before being cooled to room temperature, diluted with EtOAc (50 mL) and poured into ice water (50 g). The resulting biphasic mixture was stirred ten minutes, and then the separated aqueous layer was further extracted twice. The combined organic phases were washed with 10% aqueous sodium bicarbonate (30 mL) and brine, dried (Na₂SO₄), filtered and concentrated. The residue was slurried with acetonitrile (100 mL) at RT overnight. The solids were collected by filtration with an acetonitrile rinse and dried under vacuum to give the titled compound. ¹H NMR (400 MHz, CDCl₃) δ ppm 8.19-8.14 (m, 2H), 7.22-7.16 (m, 2H), 3.77 (hept, J=6.8 Hz, 1H), 2.58 (s, 3H), 1.47 (d, J=6.8 Hz, 6H); MS (DCI) m/z 338 (M+H)⁺.

Step 3: methyl 4-chloro-1-(4-fluorophenyl)-5-methyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

To 4,6-dichloro-1-(4-fluorophenyl)-5-methyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine (1.0 g, 2.96 mmol) and Pd-dppf (Heraeus) (45 mg, 0.062 mmol) in a 50 mL Hast C reactor was added MeOH (15 mL) and NEt₃ (0.845 mL, 6.06 mmol). The reactor was flushed with argon several times followed by carbon monoxide, then heated at 60° C. for 8 hours at 70 psi. The reaction mixture was concentrated and filtered through silica (CH₂Cl₂). The filtrate was concentrated and filtered again through silica (50% CH₂Cl₂/heptane). The filtrate from this second column was concentrated, and the resulting solids were slurried in 1:3 MTBE/heptane, collected by filtration, rinsed with more 1:3 solution and dried under vacuum to give the titled compound. ¹H NMR (400 MHz, CDCl₃) δ ppm 8.26-8.20 (m, 2H), 7.22-7.15 (m, 2H), 4.02 (s, 3H), 3.83 (hept, J=6.9 Hz, 1H), 2.58 (s, 3H), 1.49 (d, J=6.9 Hz, 6H); MS (DCI) m/z 362 (M+H)⁺.

Step 4: 4-chloro-1-(4-fluorophenyl)-5-methyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Methyl 4-chloro-1-(4-fluorophenyl)-5-methyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (543 mg, 1.5 mmol) was sonicated in DMSO (3.0 mL). The suspension was treated with aqueous 3 M NaOH (1.0 mL, 3 mmol), then stirred at RT for 100 minutes and quenched with aqueous 1 M citric acid (3.0 mL). The mixture was extracted thrice with 1:2 EtOAc/MTBE, and the combined extracts were washed with aqueous 0.5 M citric acid, dried (Na₂SO₄), concentrated and chromatographed on silica (20% EtOAc in 1:1 CH₂Cl₂/heptane) to give the titled compound. ¹H NMR (400 MHz, CDCl₃) δ ppm 7.98-7.91 (m, 2H), 7.28-7.22 (m, 2H), 3.87 (hept, J=6.8 Hz, 1H), 2.94 (s, 3H), 1.50 (d, J=6.8 Hz, 6H).

TABLE VIII List of halogenated pyrazolopyridine Int. Structure Name SM method MW Mes HP01

ethyl 4-chloro- 3-isopropyl-1- (m- tolyl)pyrazolo [3,4-b]pyridine- 6-carboxylate AMP07 H1 Specific example   357- 359   358- 360 HP02

methyl 4- chloro-3- cyclobutyl-1- phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate AMP29 H2 Specific example   341- 343   342- 344 HP03

ethyl 4-chloro- 1-[3- (dimethylamino) phenyl]-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate AMP06 H1 (steps 1 to 8) and H1′ (step 9) Specific example   386- 388   387- 389 HP04

ethyl 4-chloro- 1-cyclohexyl- 3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate AMP23 H1 (steps 1 to 8) and H1′ (step 9)   349- 351   350- 352 HP05

methyl 4- chloro-1-(4- fluorophenyl)- 3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate AMP13 H2   347- 349   348- 350 HP06

ethyl 1-[(2,4- dimethoxyphen- yl)methyl]-4- hydroxy-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate AMP28 H3 (steps 1 & 2 only) 399 400 HP07

4-chloro-1-[3- (dimethylamino) phenyl]-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylic acid HP03 J1   358- 360   359- 361 HP08

ethyl 4-chloro- 3-isopropyl- 1H- pyrazolo[3,4- b]pyridine-6- carboxylate AMP28 H3 Specific example   267- 269   268- 270 HP09

ethyl 4-chloro- 1-(4- fluorophenyl)- 3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP08, 1765- 93-1 I4   361- 363   362- 364 HP10

4-chloro-3- cyclobutyl-1- phenyl- pyrazolo[3,4- b]pyridine-6- carboxylic acid HP02 J1   327- 329   328- 330 HP11

4-chloro-1-(4- fluorophenyl)- 3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylic acid HP05 J1   333- 335   334- 336 HP12

methyl 4- chloro-1- cyclohexyl-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate AMP23 Specific example   335- 337   336- 338 HP13

ethyl 4-chloro- 3-methyl-1- phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate 1131- 18-6 Specific example   315- 317   316- 318 HP14

ethyl 3- cyclobutyl-1- [(2,4- dimethoxyphen- yl)methyl]-4- (trifluoromethyl- sulfonyloxy) pyrazolo[3,4- b]pyridine-6- carboxylate HP15 Specific example 543 544 HP15

ethyl 3- cyclobutyl-1- [(2,4- dimethoxyphen- yl)methyl]-4- hydroxy- pyrazolo[3,4- b]pyridine-6- carboxylate AMP36 H3 (steps 1 & 2 only)¹ 411 412 HP16

4-chloro-3- isopropyl-1- (m- tolyl)pyrazolo [3,4-b]pyridine- 6-carboxylic acid HP01 J1   329- 331   330- 332 HP17

4-chloro-3- methyl-1- phenyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylic acid HP13 J1 Specific example 287 HP18

4-chloro-3- methyl-1- phenyl- pyrazolo[3,4- b]pyridine-6- carbonitrile 1131- 18-6 Specific example   268- 270   269- 271 HP19

methyl 4- chloro-3- cyclobutyl-1- (4- fluorophenyl)- 1H- pyrazolo[3,4- b]pyridine-6- carboxylate AMP93 Specific example 359 and 361 360 and 362 HP20

ethyl 1-tert- butyl-3- cyclobutyl-4- [(trifluorometh- anesulfonyl) oxy]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate AMP94 Specific example 449 450 HP21

1-(4- fluorophenyl)- 3-[(propan-2- yl)oxy]-1H- pyrazolo[3,4- b]pyridine-4,6- diol AMP96 Specific example 303 304 HP22

1-(4- fluorophenyl)- 3-[(propan-2- yl)oxy]-1H- pyrazolo[3,4- b]pyridine-4,6- diyl bis(trifluoro- methanesulfonate) HP21 Specific example 567 568 HP25

methyl 4- chloro-3- cyclobutyl-1- cyclohexyl- 1H- pyrazolo[3,4- b]pyridine-6- carboxylate AMP35 Specific example 347 348 HP26

4-chloro-3- cyclobutyl-1- (4- fluorophenyl)- 1H- pyrazolo[3,4- b]pyridine-6- carboxylic acid HP19 J1 345 346 HP27

4-chloro-1-(4- fluorophenyl)- 5-methyl-3- (propan-2-yl)- 1H- pyrazolo[3,4- b]pyridine-6- carboxylic acid AMP13 Specific example 347 346 (M − H)⁻ HP28

4-chloro-1- cyclohexyl-3- (propan-2-yl)- 1H- pyrazolo[3,4- b]pyridine-6- carboxylic acid HP12 J1   321- 323   322- 324 ¹Step 2 performed in Dowtherm ™ at 160° C. for 48 h.

Synthesis of Esters and the Intermediates to Prepare Them Synthesis of AMI01: 4-(methoxymethyl)piperidin-4-ol hydrochloride

Step 1: 4-Hydroxy-4-methoxymethyl-piperidine-1-carboxylic acid tert-butyl ester

A suspension of tert-butyl 1-oxa-6-azaspiro[2.5]octane-6-carboxylate (CAS: 147804-30-6, 200 mg, 0.94 mmol) and sodium methoxide (61 mg, 1.13 mmol) in methanol (2 mL) was placed in a sealed tube and was heated at 100° C. for 20 hours. The reaction mixture was cooled to RT, acidified with acetic acid to pH 5-6, diluted with DCM and washed with water. The organic phase was separated using a phase separator and concentrated in vacuo. The titled compound was used as such in the next step without any further purification.

Step 2: 4-Methoxymethyl-piperidin-4-ol hydrochloride

4-Hydroxy-4-methoxymethyl-piperidine-1-carboxylic acid tert-butyl ester (206 mg, 0.84 mmol) was dissolved in dioxane (2 mL). 4 M HCl in dioxane (1.05 mL, 4.2 mmol) was added, and the solution was stirred at RT for 20 hours. The solvent was evaporated under reduced pressure. The titled compound was used as such in the next step without any further purification.

Synthesis of AMI02: 4-[(1,1-dioxo-1,4-thiazinan-4-yl)methyl]piperidin-4-ol hydrochloride

Step 1: tert-butyl 4-[(1,1-dioxo-1,4-thiazinan-4-yl)methyl]-4-hydroxy-piperidine-1-carboxylate

A solution of tert-butyl 1-oxa-6-azaspiro[2.5]octane-6-carboxylate (CAS: 147804-30-6, 150 mg, 0.7 mmol) and thiomorpholine 1,1-dioxide (CAS: 39093-93-1, 380 mg, 2.8 mmol) in ethanol (2 mL) was placed in a sealed tube and was heated at 75° C. for 20 hours. The reaction mixture was cooled to RT, diluted with DCM and washed with water. The organic phase was separated using a phase separator and concentrated in vacuo. The titled compound was obtained by flash column chromatography eluting with DCM/MeOH.

Step 2: 4-[(1,1-dioxo-1,4-thiazinan-4-yl)methyl]piperidin-4-ol hydrochloride

tert-Butyl 4-[(1,1-dioxo-1,4-thiazinan-4-yl)methyl]-4-hydroxy-piperidine-1-carboxylate (215 mg, 0.62 mmol) was dissolved in dioxane (2 mL). 4 M HCl in dioxane (0.89 mL, 3.6 mmol) was added, and the solution was stirred at RT for 20 hours. The solvent was evaporated under reduced pressure. The titled compound was used as such in the next step without any further purification.

Synthesis of AMI03: (2S)-2-fluoro-N,N-dimethyl-2-(4-piperidyl)ethanamine hydrochloride

Step 1: (S)-tert-butyl 4-(1-fluoro-2-oxoethyl)piperidine-1-carboxylate

To a suspension of N-fluoro-N-(phenyl sulfonyl)benzenesulfonamide ((CAS 133745-75-2, 347 g, 1100 mmol) and (5R)-(+)-2,2,3-trimethyl-5-benzyl-4-imidazolidinone dichloroacetic acid (CAS 857303-87-8, 76 g, 220 mmol) in THF and isopropyl alcohol at −20° C. was added a solution of tert-butyl 4-(2-oxoethyl)piperidine-1-carboxylate (250 g, 1100 mmol, CAS: 142374-19-4) in THF. The mixture was stirred at 10° C. for 16 h, diluted with hexane at −78° C. and filtered through silica, washed with hexane, then with saturated aqueous NaHCO₃ solution, dried, filtered, and concentrated to give (S)-tert-butyl 4-(1-fluoro-2-oxoethyl)piperidine-1-carboxylate.

Step 2: (S)-tert-butyl 4-(1-fluoro-2-hydroxyethyl)piperidine-1-carboxylate

A solution of (S)-tert-butyl 4-(1-fluoro-2-oxoethyl)piperidine-1-carboxylate (10 g, 40.8 mmol) in dichloromethane (280 mL) and ethanol (220 mL) was stirred at 10° C. Then, sodium borohydride (CAS 16940-66-2, 4.0 g, 105.7 mmol, 2.6 equiv) was added. The mixture was stirred at 10° C. for 1 hour, was diluted with water and extracted with dichloromethane. The organic layer was dried, filtered and concentrated, and the residue was purified by chromatography on silica gel (petroleum ether:ethyl acetate) to give (S)-tert-butyl 4-(1-fluoro-2-hydroxyethyl)piperidine-1-carboxylate.

Step 3: (S)-tert-butyl 4-(2-(benzylamino)-1-fluoroethyl)piperidine-1-carboxylate

Trifluoromethanesulfonic anhydride (CAS 358-23-6, 5.70 g, 20.22 mmol, 1.0 equiv) was added to a solution of (S)-tert-butyl 4-(1-fluoro-2-hydroxyethyl)piperidine-1-carboxylate (5 g, 20.22 mmol) and 2,6-dimethylpyridine (CAS 108-48-5, 2.166 g, 20.22 mmol, 1.0 equiv) in dichloromethane at 0° C. The mixture was stirred at 0° C. for 0.5 h. A separated round bottom flask was charged with benzylamine (2.166 g, 20.22 mmol, 1.0 equiv) in dichloromethane at 0° C. The solution of the triflate was then added slowly at 0° C. The reaction mixture was stirred at 25° C. for 12 hours, quenched with a saturated aqueous solution of sodium hydrogencarbonate, and extracted with dichloromethane. The organic fraction was concentrated. The residue was purified on silica gel chromatography, eluting with acetone/dichloromethane to give (S)-tert-butyl 4-(2-(benzylamino)-1-fluoroethyl)piperidine-1-carboxylate.

Step 4: (S)-tert-butyl 4-(2-amino-1-fluoroethyl)piperidine-1-carboxylate

To a solution of (S)-tert-butyl 4-(2-(benzylamino)-1-fluoroethyl)piperidine-1-carboxylate (4.5 g, 13.38 mmol) in methanol was added Pd/C, then the solution was stirred at 35° C. under hydrogen atmosphere (45 psi) for 12 hours. The mixture was filtered and concentrated to give (S)-tert-butyl 4-(2-amino-1-fluoroethyl)piperidine-1-carboxylate.

Step 5: (S)-tert-butyl 4-(2-(dimethylamino)-1-fluoroethyl)piperidine-1-carboxylate

To a mixture of (S)-tert-butyl 4-(2-amino-1-fluoroethyl)piperidine-1-carboxylate (3.0 g, 12.18 mmol) in methanol was added paraformaldehyde (CAS 30525-89-4, 1.828 g, 60.9 mmol, 5.0 equiv) followed by three drops of acetic acid. The reaction mixture stirred for 1 hour. Then sodium cyanoborohydride (CAS 25895-60-7, 1.148 g, 18.27 mmol, 1.5 equiv) was added, and the mixture was stirred for 12 hours. The reaction mixture was filtered and concentrated, and the residue was purified by column chromatography on silica gel (DCM/MeOH) to afford (S)-tert-butyl 4-(2-(dimethylamino)-1-fluoroethyl)piperidine-1-carboxylate.

Step 6: (S)-2-fluoro-N,N-dimethyl-2-(piperidin-4-yl)ethanamine hydrochloride

To a solution of (S)-tert-butyl 4-(2-(dimethylamino)-1-fluoroethyl)piperidine-1-carboxylate (2 g, 7.29 mmol) in MeOH was added 4 N hydrogen chloride in methanol (10 mL, 40 mmol, 5.5 equiv), and the mixture was stirred at RT for 2 hours. Then the solution was concentrated to give (S)-2-fluoro-N,N-dimethyl-2-(piperidin-4-yl)ethanamine hydrochloride.

Synthesis of AMI04: 4-(ethoxymethyl)-4-fluoro-piperidine

Step 1: 1-tert-butyl 4-ethyl 4-fluoropiperidine-1,4-dicarboxylate

In a 100 mL round-bottomed flask was combined 1-tert-butyl 4-ethyl piperidine-1,4-dicarboxylate (1 g, 3.89 mmol) and THF (10 mL). The solution was cooled to −78° C., and sodium hexamethyldisilazide (6 mL of 1 M THF solution, 6.00 mmol) was added slowly via syringe. After 60 min, N-fluoro-N-(phenylsulfonyl)benzenesulfonamide (2 g, 6.34 mmol) in THF (3 mL) was added. After 2 h, dichloromethane/water (1:1, 40 mL) was added. The aqueous layer was extracted with dichloromethane, and the combined organic fractions were dried over Na₂SO₄, filtered, and concentrated in vacuo.

Step 2: tert-butyl 4-fluoro-4-(hydroxymethyl)piperidine-1-carboxylate

A solution of 1-tert-butyl 4-ethyl 4-fluoropiperidine-1,4-dicarboxylate (1.5 g, 5.45 mmol) in THF (5 mL) was cooled to 0° C., and then 1 M LiAlH₄ in THF (3.81 mL, 3.81 mmol) was added dropwise. The reaction mixture was warmed up to RT and stirred for 2 h. Water (0.9 mL) was added to the reaction mixture dropwise followed by 2 N NaOH (0.3 mL). The mixture was stirred for another 30 minutes, and then solid removed by filtration through diatomaceous earth and washed with EtOAc. The filtrate was washed with brine, dried over Na₂SO₄, and concentrated from acetonitrile under vacuum several time to remove the water to afford tert-butyl 4-fluoro-4-(hydroxymethyl)piperidine-1-carboxylate.

Step 3: tert-butyl 4-(ethoxymethyl)-4-fluoropiperidine-1-carboxylate

tert-Butyl 4-fluoro-4-(hydroxymethyl)piperidine-1-carboxylate (30 g, 129 mmol) was first treated with sodium hydride (6.17 g, 154 mmol) DMF (500 mL), and then iodoethane (24.07 g, 154 mmol) was added at room temperature. The reaction mixture was stirred at 25° C. for 12 h. The mixture was washed with H₂O and extracted with EtOAc, and then the combined organic phases were washed with H₂O, and brine. The organic fraction was dried Na₂SO₄, filtered and concentrated to give tert-butyl 4-(ethoxymethyl)-4-fluoropiperidine-1-carboxylate (26.9 g, 103 mmol, 80% purity).

Step 4: 4-(ethoxymethyl)-4-fluoro-piperidine

A mixture of tert-butyl 4-(ethoxymethyl)-4-fluoropiperidine-1-carboxylate 26.9 g, 103 mmol) in ethyl acetate (200 mL) was made acidic by addition of HCl in ethyl acetate solution at 0° C. Then the mixture was allowed to warm to 15° C. and stirred at 15° C. for 3 h. The reaction mixture was concentrated under vacuum to yield 4-(ethoxymethyl)-4-fluoropiperidine as a hydrochloride salt (15.27 g, 95 mmol, 92% yield).

Synthesis of AMI05: 4-fluoro-4-(2-methoxyethoxymethy)piperidine

Step 1: tert-butyl 4-fluoro-4-((2-methoxyethoxy)methyl)piperidine-1-carboxylate

To a mixture of tert-butyl 4-fluoro-4-(hydroxymethyl)piperidine-1-carboxylate (30 g, 129 mmol, prepared as described in the synthesis of AMI04) in DMF (400 mL) was added sodium hydride (6.43 g, 161 mmol) at 0° C. After 15 minutes, 1-bromo-2-methoxyethane (35.7 g, 257 mmol) was added at 0° C., and the mixture was stirred at 25° C. for 12 h. The mixture was quenched with 200 mL of aqueous NH₄Cl at 5° C. The organic layer was separated, washed with water and brine, dried over Na₂SO₄, and concentrated. After column chromatography on silica gel (petroleum ether/EtOAc=10:1 to petroleum ether/EtOAc=2:1), tert-butyl 4-fluoro-4-((2-methoxyethoxy)methyl)piperidine-1-carboxylate (20.5 g, 70.4 mmol, 54.% yield) was obtained.

Step 2: 4-fluoro-4-(2-methoxyethoxymethy)piperidine

A solution of tert-butyl 4-fluoro-4-((2-methoxyethoxy)methyl)piperidine-1-carboxylate (20 g, 68.6 mmol) in 200 mL EtOAc was made acidic with HCl in EtOAc at room temperature. After TLC on silica gel (petroleum ether/EtOAc=1:1) showed that the reaction was complete, the mixture was concentrated to afford the titled compound as a hydrochloride salt (15 g, 65.9 mmol, 96% yield).

Synthesis of AMI07: 4-fluoro-4-(methoxymethyl)piperidine

Step 1: tert-butyl 4-fluoro-4-(methoxymethyl)piperidine-1-carboxylate

To a mixture of tert-butyl 4-fluoro-4-(hydroxymethyl)piperidine-1-carboxylate (30 g, 129 mmol, prepared as described in the synthesis of AMI04) and NaH (3.09 g, 129 mmol) in THF (500 mL) was added iodomethane (41.9 g, 295 mmol) at room temperature, and then the mixture was stirred at 25° C. for 12 h, The reaction mixture was diluted with water and extracted with EtOAc. The combined organic phases were washed with water and brine. The organic fraction was dried over Na₂SO₄, filtered, and concentrated under vacuum. The residue was purified on a silica gel column eluted with petroleum ether/EtOAc=2:1 to give tert-butyl 4-fluoro-4-(methoxymethyl)piperidine-1-carboxylate (25 g, 101 mmol, 79% yield).

Step 2: 4-fluoro-4-(methoxymethyl)piperidine

A mixture of tert-butyl 4-fluoro-4-(methoxymethyl)piperidine-1-carboxylate (25 g, 101 mmol) in EtOAc (300 mL) was made acidic with HCl in EtOAc at 0° C., and the mixture was allowed to warm to 15° C. and stirred at 15° C. for 3 h. The reaction mixture was concentrated under vacuum to yield the titled compound as a hydrochloride salt (13 g, 70.8 mmol, 70.0% yield).

Synthesis of AMI08: 3-fluoro-3-(2-methoxyethoxymethy)piperidine

Step 1: tert-butyl 3-fluoro-3-((2-methoxyethoxy)methyl)piperidine-1-carboxylate

To a mixture of tert-butyl 3-fluoro-3-(hydroxymethyl)piperidine-1-carboxylate (25 g, 107 mmol) in THF (300 mL) was added NaH (2.57 g, 107 mmol) at 0° C. After 15 minutes, 1-bromo-2-methoxyethane (29.8 g, 214 mmol) was added at 0° C. The mixture was stirred at 25° C. for 12 h, and then the reaction was quenched by the addition of saturated aqueous NH₄Cl and extracted with EtOAc. The combined organic phases were washed with water and brine, dried over Na₂SO₄, filtered and concentrated in vacuum. The residue was added to a silica gel column eluted with hexanes:ethyl acetate (2:1) to give tert-butyl 3-fluoro-3-((2-methoxyethoxy)methyl)piperidine-1-carboxylate (22 g, 76 mmol, 70.5% yield).

Step 2: 3-fluoro-3-(2-methoxyethoxymethyl)piperidine

A mixture of tert-butyl 3-fluoro-3-((2-methoxyethoxy)methyl)piperidine-1-carboxylate (25 g, 86 mmol) in EtOAc (200 mL) was made acidic with HCl in EtOAc at 0° C. The mixture was allowed to warm to 15° C. and stirred at 15° C. for 3 h. The reaction mixture was concentrated under vacuum to the titled compound as a hydrochloride salt (15 g, 65.9 mmol, 77% yield).

Synthesis of AMI09: 2-(4-hydroxy-4-piperidyl)acetonitrile hydrochloride

Step 1: tert-butyl 4-(cyanomethyl)-4-hydroxy-piperidine-1-carboxylate

A flame-dried round bottom flask was cooled down to RT under argon. A solution of 1 M LiHMDS in THF (1.51 mL, 3.02 mmol, 2.0 equiv) was introduced into the flask and cooled down to −78° C. (acetone/dry ice bath). Dry MeCN (157 μL, 3.02 mmol, 2.0 equiv) in anhydrous THF (5 mL) was then added dropwise under argon, and the reaction mixture was stirred for 45 minutes at −78° C. At this point, a solution of 1-(tert-butoxycarbonyl)-4-piperidone (300 mg, 1.51 mmol, 1.0 equiv) in dry THF (5 mL) was added dropwise, and the reaction mixture was stirred at −78° C. for 1 h. The reaction mixture was quenched with an aqueous saturated solution of ammonium chloride and diluted with ethyl acetate. The two phases were separated, and the aqueous phase was extracted with ethyl acetate. The combined organic layers were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford tert-butyl 4-(cyanomethyl)-4-hydroxypiperidine-1-carboxylate which was used as such in the next step.

Step 2: 2-(4-hydroxy-4-piperidyl)acetonitrile hydrochloride

tert-Butyl 4-(cyanomethyl)-4-hydroxypiperidine-1-carboxylate (226 mg, 0.94 mmol, 1 equiv) was dissolved in dioxane (2.5 mL). 4 M HCl in dioxane (1.41 mL, 1.88 mmol, 6 equiv) was added, and the solution was stirred at RT for 5 days. The reaction mixture was concentrated under reduced pressure. The titled compound was used as such without any further purification.

Synthesis of AMI10: 4-methoxy-1,4′-bipiperidine

Step 1: benzyl 4-methoxy-[1,4′-bipiperidine]-1′-carboxylate

To a solution of benzyl 4-oxopiperidine-1-carboxylate ([19099-93-5], 40 gram, 171 mmol) and 4-methoxypiperidine ([4045-24-3], 24.6 gram) in dichloromethane (800 mL) was added acetic acid (10.8 mL, 189 mmol) and sodium triacetoxyborohydride (54.5 gram, 257 mmol). The mixture was stirred at 0° C. for 120 minutes. Next, the mixture was washed with a saturated aqueous K₂CO₃ solution. The organic phase was separated and concentrated to give a residue that was purified by chromatography on silica gel using a gradient elution with CH₂Cl₂ to CH₂Cl₂/CH₃OH (100/0 to 97/2.5) to give the titled compound.

Step 2: 4-methoxy-1, 4′-bipiperidine

Benzyl 4-methoxy-[1,4′-bipiperidine]-1′-carboxylate (23 gram, 69 mmol) was dissolved in CH₃OH (350 mL). The solution was flushed with N₂ and 10% Pd/C (7.3 gram, 6.9 mmol) was added. After applying a balloon with H₂, the mixture was stirred at ambient temperature overnight. Next, the mixture was filtered through diatomaceous earth, and the resulting filtrate was concentrated to give the titled compound.

Synthesis of AMI11: 1-piperidin-1-ium-4-ylpiperidine-4-carbonitrile chloride

Step 1: tert-butyl 4-(4-cyano-1-piperidyl)piperidine-1-carboxylate

A suspension of 4-cyanopiperidine ([4395-98-6], 500 mg, 4.5 mmol), tert-butyl 4-oxopiperidine-1-carboxylate ([79099-07-3], 900 mg, 4.5 mmol) and AcOH (0.27 mL) in DCM (66 mL) was cooled at 0° C. Next, sodium triacetoxyborohydride ([56553-60-7], 955 mg, 4.5 mmol) was added portion wise. After overnight stirring, the reaction was diluted with 60 mL of water together with a 1 N citric acid solution to bring down the pH till 3-4. The organic layer was separated and discarded. Next, the aqueous layer was brought to neutral pH with a saturated aqueous NaHCO₃ solution. After extraction with DCM, the organic phase was concentrated to give the titled compound.

Step 2: 1-piperidin-1-ium-4-ylpiperidine-4-carbonitrile chloride

tert-Butyl 4-(4-cyano-1-piperidyl)piperidine-1-carboxylate (662 mg, 2.26 mmol) was dissolved in DCM and trifluoroacetic acid ([76-05-1], 0.93 mL) was added. After overnight stirring, the mixture was concentrated to dryness. The obtained residue was suspended in 4 N HCl in dioxane. The addition of ethanol gave a suspension which was filtered to give the titled compound as a precipitate.

Synthesis of ALC02: (2R)-2-fluoro-2-tetrahydropyran-4-yl-ethanol

Step 1: (2R)-2-fluoro-2-tetrahydropyran-4-yl-acetaldehyde

To a mixture of (R)-5-benzyl-2,2,3-trimethylimidazolidin-4-one dichloroacetic acid salt (CAS 857303-87-8, 2.71 g, 7.80 mmol, 0.2 equiv) and N-fluoro-N-(phenylsulfonyl)benzenesulfonamide (CAS 133745-75-2, 12.30 g, 39 mmol, 1.0 equiv) in THF (200 mL) and isopropyl alcohol (25 mL) was slowly added at −20° C. a solution 2-(tetrahydro-2H-pyran-4-yl)acetaldehyde (5 g, 39 mmol, CAS 65626-23-5) in THF (25 mL). The mixture was stirred at −20° C. for 12 hours, then diluted with hexane (800 mL) cooled to −78° C. and filtered through silica, washed with hexane. The filtrate was concentrated to give (R)-2-fluoro-2-(tetrahydro-2H-pyran-4-yl)acetaldehyde.

Step 2: (2R)-2-fluoro-2-tetrahydropyran-4-yl-ethanol

To a solution of (R)-2-fluoro-2-(tetrahydro-2H-pyran-4-yl)acetaldehyde (4 g, 27.4 mmol) in dichloromethane (48 mL) and ethanol (40 mL) was added sodium borohydride (CAS 16940-66-2, 2.59 g, 68.4 mmol, 2.5 equiv). The mixture was stirred at 25° C. for 12 hours, then diluted with water and extracted with dichloromethane. The organic layer was dried, filtered, concentrated and purified by chromatography (petroleum ether, ethylate) to give (2R)-2-fluoro-2-tetrahydropyran-4-yl-ethanol.

Synthesis of ALC03: 1-[4-fluoro-4-(hydroxymethyl)-1-piperidyl]ethanone

Step 1: tert-butyl 4-(bromomethyl)-4-fluoropiperidine-1-carboxylate

To a mixture of tert-butyl 4-methylenepiperidine-1-carboxylate (159635-49-1, 50 g, 253 mmol) and triethylamine trihydrofluoride (102 g, 634 mmol) in dichloromethane (1 L) was added 1-bromopyrrolidine-2,5-dione (67.7 g, 380 mmol) at 0° C. After 15 min, stirring was continued at 20° C. for 3 h. Then the mixture was poured into ice-water, neutralized with aqueous 28% ammonia and extracted with dichloromethane. The combined extracts were washed with ˜0.1 N HCl and with 5% aqueous sodium hydrogencarbonate solution, dried with sodium sulfate, filtered and concentrated. The residue was purified by column chromatography to provide tert-butyl 4-(bromomethyl)-4-fluoropiperidine-1-carboxylate (60.1 g, 203 mmol, 80% yield).

Step 2: tert-butyl 4-(acetoxymethyl)-4-fluoropiperidine-1-carboxylate

To a mixture of tert-butyl 4-(bromomethyl)-4-fluoropiperidine-1-carboxylate (50 g, 169 mmol) and potassium iodide (7.01 g, 42.2 mmol) in dimethyl formamide (1.5 L) was added potassium acetate (249 g, 2532 mmol) at room temperature. The mixture was stirred at 120-140° C. for 12 h, then cooled, diluted with water, and extracted with ethyl acetate. The combined organic phases were washed with water and brine. The organic layer was dried over Na₂SO₄, filtered, and concentrated in vacuo. The residue was purified by chromatography on a silica gel column eluted with hexanes:ethyl acetate to give tert-butyl 4-(acetoxymethyl)-4-fluoropiperidine-1-carboxylate (42 g, 153 mmol, 90% yield).

Step 3: (4-fluoropiperidin-4-yl)methyl acetate hydrochloride

To a mixture of tert-butyl 4-(acetoxymethyl)-4-fluoropiperidine-1-carboxylate (50 g, 182 mmol) in ethyl acetate (400 mL) was added a solution of HCl (1 L) at 0° C. The mixture was allowed to warm to 15° C. and stirred at 15° C. overnight. The reaction mixture was concentrated under vacuum, and the residue washed with dichloromethane. Then the precipitate was collected by filtration to obtain (4-fluoropiperidin-4-yl)methyl acetate hydrochloride (33 g, 156 mmol, 86% yield).

Step 4: (1-acetyl-4-fluoropiperidin-4-yl)methyl acetate

To a solution of (4-fluoropiperidin-4-yl)methyl acetate hydrochloride (30 g, 142 mmol) and triethylamine (59.3 mL, 425 mmol) in dichloromethane (300 mL) was added acetyl chloride (16.69 g, 213 mmol) at 0° C. The mixture was stirred overnight at 20° C., then diluted with dichloromethane and washed with water. The dichloromethane layer was concentrated to give crude (1-acetyl-4-fluoropiperidin-4-yl)methyl acetate (21 g, 97 mmol, 68.2% yield).

Step 5: 1-[4-fluoro-4-(hydroxymethyl)-1-piperidyl]ethanone

(1-Acetyl-4-fluoropiperidin-4-yl)methyl acetate (30.8 g, 142 mmol) was dissolved in 3:1 THF:water (400 mL) at 0° C., and then lithium hydroxide (6.80 g, 284 mmol) was added in one portion. The reaction mixture was stirred for 1 hour at 0° C. The mixture was poured into ethyl acetate and water, shaken, and the layers separated. The aqueous layer was extracted with ethyl acetate. The ethyl acetate extracts were combined, dried over Na₂SO₄, and concentrated under reduced pressure. The residue was titrated with CH₂Cl₂ and cyclohexane to afford 1-[4-fluoro-4-(hydroxymethyl)-1-piperidyl]ethanone (19 g, 108 mmol, 76% yield).

Alternatively, 1-[4-fluoro-4-(hydroxymethyl)-1-piperidyl]ethanone is available by treatment of commercially available (4-fluoropiperidin-4-yl)methanol (CAS: 949100-11-2) with acetic anhydride.

Synthesis of ALC04: 2-[isopropyl(oxetan-3-yl)amino]ethanol

2-[Isopropyl(oxetan-3-yl)amino]ethanol is available by the reaction of (isopropylamino)ethanol (CAS: 109-56-8) with 1 equivalent of 3-oxetanone (CAS: 6704-31-0) in a solvent such as isopropanol or THF with a reducing agent such as sodium borohydride or sodium triacetoxyborohydride, followed by distillation.

Synthesis of ALC05: 2-(oxetan-3-yloxy)ethanol

Step 1: 3-(2-(benzyloxy)ethoxy)oxetane

1.0 M Lithium bis(trimethylsilyl)amide in THF (31.1 mL, 31.1 mmol, 1.2 equiv) was added dropwise at RT to a solution of oxetan-3-ol (1.92 g, 25.9 mmol) and ((2-bromoethoxy)methyl)benzene (6.13 g, 28.5 mmol, 1.1 equiv) in dioxane (15 mL). The mixture was stirred at ambient temperature for 2 hours. DMF (20 mL) was added along with sodium iodide, and the reaction mixture was stirred at ambient temperature overnight, then stirred at 70° C. for 20 hours. The reaction mixture was concentrated under reduced pressure, and the residue was partitioned between ethyl acetate and aqueous citric acid. The organic layer was washed twice with brine, then dried over MgSO₄, filtered and concentrated. The residue was purified by column chromatography on silica gel (dichloromethane and ethyl acetate) to give 3-(2-(benzyloxy)ethoxy)oxetane.

Step 2: 2-(oxetan-3-yloxy)ethanol

To a solution of 3-(2-(benzyloxy)ethoxy)oxetane (1.40 g, 6.72 mmol) in THF (28 mL) was added 20% palladium hydroxide on carbon (0.178 g, 0.645 mmol) in a 50 mL pressure bottle, and the mixture was stirred for 4 h under a hydrogen atmosphere. The reaction mixture was filtered free of catalyst and solids, and the filtrate was concentrated under reduced pressure. The residue was purified by silica gel chromatography eluting with a mixture of ethyl acetate and dichloromethane to give the titled compound.

Synthesis of intermediate BF01: potassium trifluorido{[4-(methoxymethyl)piperidin-1-yl]methyl}borate

4-(Methoxymethyl)piperidine hydrochloride ([916317-00-5], 1.0 g, 6.03 mmol,), potassium bromomethyl trifluoroborate (1.21 g, 6.03 mmol), KHCO₃ (1.2 g, 12.1 mmol) and KI (100 mg, 0.6 mmol) were stirred under N₂ in dry THF (8 mL) at 80° C. for 4 hours. The reaction mixture was cooled to room temperature and concentrated in vacuo. The residue was suspended in dry acetone and filtered. The filtrate was treated with diethyl ether, and the resulting precipitate was collected by filtration and dried to afford the titled compound, which was used as such in the next step.

TABLE IX List of BF₃ salts Int. Structure Name SM method MW Mes BF01

potassium trifluorido{[4- (methoxymeth- yl)piperidin-1- yl]methyl}borate 916317- 00-5 and 888711- 44-2 Specific example 249

TABLE X List of amines Int. Structure Name SM method MW Mes AMI01

4- (methoxymeth- yl)piperidin-4- ol hydrochloride 147804- 30-6 Specific example 181 AMI02

4-[(1,1-dioxo- 1,4-thiazinan- 4- yl)methyl] piperidin-4-ol hydrochloride 147804- 30-6 Specific example 284 AMI03

(2S)-2-fluoro- N,N-dimethyl- 2-(4- piperidyl)ethan- amine hydrochloride 142374- 19-4 Specific example 210 AMI04

4- (ethoxymethyl)- 4-fluoro- piperidine 142851- 03-4 Specific example 161 AMI05

4-fluoro-4-(2- methoxyethoxy- methyl)piperidine 614730- 97-1 Specific example 191 AMI06 955082- 95-8 or 955028- 84-9 (HCl salt)

(3R,4R)-3- fluoropiperidin- 4-ol 119 AMI07

4-fluoro-4- (methoxymeth- yl)piperidine 614730- 97-1 Specific example 147 AMI08

3-fluoro-3-(2- methoxyethoxy- methyl)piperidine 1209781- 11- 2 Specific example 191 AMI09

2-(4-hydroxy- 4- piperidyl)aceto- nitrile hydrochloride 79099- 07-3 Specific example 140 AMI10

4-methoxy- 1,4′- bipiperidine 19099- 93-5 and 4045- 24-3 Specific example 198 AMI11

1-piperidin- 1-ium-4- ylpiperidine- 4- carbonitrile chloride 79099- 07-3 and 4395- 98-6 Specific example 249

TABLE XI List of alcohols Int. Structure Name SM method MW Mes ALC01

(2S)-2-fluoro- 2- tetrahydropyran- 4-yl-ethanol Analogous to ALC02 148 ALC02

(2R)-2-fluoro- 2- tetrahydropyran- 4-yl-ethanol 65626- 23-5 Specific example 148 ALC03

1-[4-fluoro-4- (hydroxymethyl)- 1- piperidyl]ethan- one 159635- 49-1 Specific example 175 ALC04

2- [isopropyl(oxetan- 3- yl)amino]ethan- ol Specific example 159 ALC05

2-(oxetan-3- yloxy)ethanol Specific example 118 ALC06

(1- cyclobutyl- 4- piperidyl) methanol 6457- 49-4 and 1191- 95-3 I30 169 170 ALC07

(1- cyclohexyl- 4- piperidyl) methanol 6457- 49-4 and 108- 94-1 I30 197 198 ALC08

(1- tetrahydro- pyran-4-yl-4- piperidyl) methanol 6457- 49-4 and 29943- 42-8 I30 199 200 ALC09

(1- cyclopropyl- 4- piperidyl) methanol 6457- 49-4 and 27374- 25-0 I26 155 156

Synthesis of BOR1: 1-[5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2-pyridyl]piperidine-4-carbonitrile

Step 1: 1-(5-bromo-2-pyridyl)piperidine-4-carbonitrile

Potassium carbonate (35.3 g, 256 mmol) was added at RT to a solution of 5-bromo-2-fluoropyridine (CAS: 766-11-0, 15 g, 85 mmol) and 4-cyanopiperidine (CAS: 4395-98-6, 14.1 g, 128 mmol) in DMSO (100 mL). The reaction mixture was heated at 100° C. for 6 hours and cooled down to RT. Water (200 mL) was added, and the precipitate was collected by filtration, washed with water and dried at 40° C. under reduced pressure.

Step 2: 1-[5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2-pyridyl]piperidine-4-carbonitrile

Potassium acetate (13.6 g, 138 mmol) in a round bottom flask was dried at 100° C. under a flow of nitrogen. The solid was left under nitrogen cooling down to RT. Anhydrous dioxane (250 mL) was added, and nitrogen was bubbled through the suspension for 30 minutes. Palladium(II) acetate (760 mg, 3.4 mmol), Sphos (CAS: 657408-07-6, 3.5 g, 8.5 mmol), bis(pinacolato)diboron (CAS: 73183-34-3, 25.8 g, 101.2 mmol), and the compound from Step 1 (15 g, 56.4 mmol) were successively added, and nitrogen was bubbled for another 1 hour at RT. The reaction mixture was heated at 60° C. for 28 hours, and then cooled down to RT. The precipitate was filtered and washed with ethyl acetate (250 mL). The organic phase was washed twice with water (2×250 mL), dried over sodium sulfate, filtered and concentrated under reduced pressure. The residue was stirred in cyclohexane, and the precipitate was filtered to yield the titled compound.

Method K: Pinacol Ester Synthesis

Step 1: SNAr

A solution of halogenated derivative (1 equiv), amine (1.1 equiv) and DIPEA (from 1.1 to 2.1 equiv) in acetonitrile is heated at 80° C. for 4 hours. Amine (from 0.5 to 1.1 equiv) and DIPEA (from 1 to 2.1 equiv) can be added in one or two times over a period of 18 to 22 hours. The reaction mixture is cooled down to RT, diluted with DCM and washed with water. The organic phase is separated using a phase separator and concentrated under reduced pressure. The residue was purified by flash column chromatography eluting with n-heptane/ethyl acetate to give the substituted product.

Step 2: Borylation

Potassium acetate (1.5 equiv) in a sealed tube is dried at 80° C. under a flow of argon. The solid is left cooling down to RT. Dioxane is added, and nitrogen is bubbled through the suspension for 15 minutes. Palladium(II) acetate (0.05 equiv), Sphos (CAS: 657408-07-6, 0.13 equiv), bis(pinacolato)diboron (CAS: 73183-34-3, 1.2 equiv), and the compound from previous step (1 equiv) are successively added, and nitrogen is bubbled for another 1 hour at RT. The reaction mixture is heated at 100° C. for 20 hours and then cooled down to RT. The precipitate is filtered and washed with ethyl acetate. The filtrate is washed twice with water, dried over sodium sulfate, filtered and concentrated under reduced pressure. The residue is either used as such or stirred in cyclohexane and the solid collected by filtration to yield the pinacol ester.

Illustrative synthesis of BOR2: 1-[5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyrimidin-2-yl]piperidine-3-carbonitrile

Step 1: 1-(5-bromopyrimidin-2-yl)piperidine-3-carbonitrile

A solution of 5-bromo-2-chloropyrimidine (CAS: 32779-36-5, 300 mg, 1.55 equiv), 3-cyanopiperidine hydrochloride (CAS:828300-57-8, 250 mg, 1.7 mmol) and DIPEA (567 μL, 3.3 mmol) in acetonitrile (3 mL) was heated at 80° C. for 4 hours. 3-Cyanopiperidine hydrochloride (CAS:828300-57-8, 125 mg, 0.85 mmol) and DIPEA (567 μL, 3.3 mmol) were again added, and the stirring at 80° C. was continued for 20 hours. The reaction mixture was diluted with DCM and washed with water. The organic phase was separated using a phase separator and concentrated under reduced pressure. The residue was purified by flash column chromatography eluting with n-heptane/ethyl acetate to give the titled compound.

Step 2: 1-[5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyrimidin-2-yl]piperidine-3-carbonitrile

Potassium acetate (449 mg, 4.6 mmol) in a sealed tube was dried at 80° C. under a flow of argon. The solid was left cooling down to RT. Dioxane (13 mL) was added, and nitrogen was bubbled through the suspension for 15 minutes. Palladium(II) acetate (34 mg, 0.15 mmol), Sphos (CAS: 657408-07-6, 156 mg, 0.4 mmol), bis(pinacolato)diboron (CAS: 73183-34-3, 928 mg, 3.6 mmol), and the compound from previous step (1.13 g, 3.05 mmol) were successively added, and nitrogen was bubbled for another 1 hour at RT. The reaction mixture was heated at 100° C. for 20 hours and then cooled down to RT. The precipitate was collected by filtration and washed with ethyl acetate. The organic phase was washed twice with water, dried over sodium sulfate, filtered and concentrated under reduced pressure to give the titled compound which was used as such without any further purification.

TABLE XII Pinacol ester coupling reagents Int. Structure Name SM method MW Mes BOR1

1-[5-(4,4,5,5- tetramethyl- 1,3,2- dioxaborolan- 2-yl)-2- pyridyl]piperidine- 4- carbonitrile 766- 11-0, 4395- 98-6 Specific example 313 314 BOR2

1-[5-(4,4,5,5- tetramethyl- 1,3,2- dioxaborolan- 2-yl)pyrimidin- 2- yl]piperidine- 3-carbonitrile 32779- 36-5, 828300- 57-8 K 314 315 BOR3

tert-butyl 4- [methyl-[5- (4,4,5,5- tetramethyl- 1,3,2- dioxaborolan- 2-yl)pyrimidin- 2- yl]amino]piper- idine-1- carboxylate 32779- 36-5, 147539- 41-1 K 418 419

Method I1-I35: Synthesis of Esters Method I1: Cyclization of Alkylidene Pyruvates and Aminopyrazoles

-   A is either N or CH -   A′ is either R^(e) or L¹-G^(3C) as described in the Summary

The alkylidene pyruvate (1 to 1.5 equiv) and the aminopyrazole (1 to 1.5 equiv) in acetic acid or DMF are stirred under air at temperatures ranging from RT to reflux for 1 h to several days. Alternatively, the reaction mixture is heated under microwave irradiation at 150° C. for 20 minutes to 2 h followed either by stirring under air in an opened flask at temperatures ranging from RT to 90° C. for 1 h to several days or by removal of the solvent in vacuo, dilution of the residue in ethanol and stirring at reflux for 1 h to several days. Then volatiles are removed in vacuo to afford the titled compound which is used as such or alternatively worked up by dilution with an organic solvent, washed successively with a basic aqueous solution and brine, dried over sodium sulfate, filtered and concentrated in vacuo and used as such or further purified either by precipitation, by preparative HPLC or by flash chromatography on silica gel.

Alternatively, the alkylidene pyruvate (1 equiv) and the aminopyrazole (1 equiv) in N-methylpyrrolidone can be heated at 80 to 100° C. over 8 to 24 hours. Next, the reaction mixture is cooled down to room temperature and a base such as Cs₂CO₃ (2-6 equiv) is added. The resulting mixture is stirred open to the air until full oxidation is observed.

Illustrative synthesis of E018: 4-(4-Cyano-3,4,5,6-tetrahydro-2H-[1,2′]bipyridinyl-5′-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid ethyl ester

The alkylidene pyruvate ALP09 (47.1 g, 150.5 mmol) and the aminopyrazole AMP29 (30 g, 140.7 mmol) were dissolved in acetic acid (240 mL) in an opened round bottom flask equipped with a condenser. The solution was heated at 80° C. for 40 hours and then left cooling down to RT. The mixture was concentrated under reduced pressure, and the crude residue was diluted with DCM (400 mL). The organic phase was washed successively with a saturated aqueous solution of Na₂CO₃ and a saturated aqueous solution of NaCl, dried over sodium sulfate, filtered and concentrated in vacuo. The crude sample was purified by flash column chromatography eluting with dichloromethane/ethyl acetate. The solid was stirred for 10 minutes in methanol, filtered and dried at 40° C. under reduced pressure to give the titled compound.

Illustrative synthesis of E425: ethyl 1-cyclohexyl-4-(4-formylphenyl)-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

A solution of ALP36 (116 mg, 0.5 mmol) and AMP95 (112 mg, 0.5 mmol) in N-methylpyrrolidine (2 mL) was heated at 100° C. for 20 hours in a sealed tube. The volatiles were removed in vacuo, and the residue was purified by flash chromatography on silica gel eluted with ethyl acetate/n-heptane (0/1 to 1/0) to give the titled compound.

Illustrative synthesis of E505: methyl 4-(4-bromophenyl)-1-cyclohexyl-3-hydroxy-1H-pyrazolo[3, 4-b]pyridine-6-carboxylate

5-Amino-1-cyclohexyl-1H-pyrazol-3-ol ([436088-86-7], 5.54 g, 30.5 mmol,) and (E)-methyl-4-(4-bromophenyl)-2-oxobut-3-enoate ([608128-34-3], 8.22 g, 30.5 mmol,) in NMP (60 mL,) were heated overnight at 90° C. Next, the reaction mixture was cooled down to room temperature and Cs₂CO₃ (30 g, 91.6 mmol) was added. The resulting mixture was stirred open to the air until full oxidation to the titled compound was observed. The obtained solution was used as such for alkylation.

Method I2: Suzuki Coupling

Method I2A

Argon is bubbled through a suspension of halogenated derivative (1 equiv), boronic acid or ester (1.3 equiv), palladium(II) acetate (0.05 equiv), Sphos (CAS: 657408-07-6, 0.12 equiv) and potassium phosphate tribasic (CAS: 7778-53-2, 3 equiv) in dioxane/water at room temperature for 15 minutes. The reaction mixture is heated at 100° C. for 30 minutes to 1 h and then cooled down to RT. The mixture is filtered, and the filtrate is either concentrated in vacuo or diluted with ethyl acetate and washed with water and brine. The organic phase is dried over sodium sulfate, filtered and concentrated under reduced pressure. The coupled compound is obtained after purification by flash column chromatography.

Illustrative synthesis of E252: ethyl 4-[6-(4-cyano-1-piperidyl)-3-pyridyl]-3-isopropyl-1-(m-tolyl)pyrazolo[3,4-b]pyridine-6-carboxylate

Argon was bubbled into a suspension of HP01 (30 mg, 0.1 mmol), BOR1 (39 mg, 0.12 mmol), palladium(II) acetate (1.1 mg, 0.005 mmol), Sphos (CAS: 657408-07-6, 5 mg, 0.01 mmol) and potassium phosphate tribasic (CAS: 7778-53-2, 60 mg, 0.29 mmol) in dioxane/water (0.7 mL/0.2 mL) at room temperature for 15 minutes. The reaction mixture was heated at 100° C. for 1 h and then cooled down to RT. The mixture was filtered; the filtrate was diluted with ethyl acetate and washed with water and brine. The organic phase was dried over sodium sulfate, filtered and concentrated under reduced pressure. The titled compound was obtained after purification by flash column chromatography eluting with n-heptane/ethyl acetate.

Method I2B

Nitrogen is bubbled into a suspension of halogenated derivative (1 equiv), boronic acid or ester (from 1.3 to 1.5 equiv), Pd(dppf)Cl₂.DCM (CAS: 95464-05-4, 0.1 equiv), and potassium carbonate (1.5 equiv) in dioxane/water at room temperature for 15 minutes. The reaction mixture is heated at a temperature ranging from 80° C. to 110° C. for 2 to 20 hours, and cooled down to RT. The mixture is filtered, and the filtrate is either concentrated in vacuo and purified by flash column chromatography or worked up by diluting with ethyl acetate and washing with water and brine. The organic phase is dried over sodium sulfate, filtered and concentrated under reduced pressure. The coupled compound is obtained after purification by flash column chromatography or used as such in the next step.

Illustrative synthesis of E308: ethyl 1-cyclohexyl-4-(1,3-dimethylpyrazol-4-yl)-3-isopropyl-pyrazolo[3,4-b]pyridine-6-carboxylate

Nitrogen was bubbled into a suspension of HP04 (50 mg, 0.14 mmol), 1,3-dimethylpyrazole-4-boronic pinacol ester (CAS: 1046832-21-6, 41 mg, 0.19 mmol), Pd(dppf)Cl₂.DCM (CAS: 95464-05-4, 12 mg, 0.014 mmol), and potassium carbonate (30 mg, 0.21 mmol) in dioxane/water (1 mL/0.3 mL) at room temperature for 15 minutes. The reaction mixture was heated at 110° C. for 2 hours, and cooled down to RT. The mixture was filtered and concentrated in vacuo. The titled compound was obtained after purification by flash column chromatography eluting with n-heptane/ethyl acetate.

Method I3: Nucleophilic Substitutions of Amines

A mixture of the chloride or triflate pyrazolopyridine intermediate (1.0 equiv), the amine as free base or hydrochloride salt (from 1 to 10 equiv) and DIPEA (from 1 to 15 equiv) in anhydrous acetonitrile and DMSO in a sealed tube or a round bottom flask is heated at a temperature ranging from 50 to 130° C. for 1 h to several days (up to 8 days). The reaction mixture is cooled to RT, and volatiles are removed in vacuo. The resulting residue is either purified by precipitation or by flash chromatography on silica gel to afford the titled compound or alternatively partitioned between either dichloromethane or ethyl acetate and water. The two phases are then separated, and the aqueous phase is extracted with either ethyl acetate or dichloromethane. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo and the resulting crude mixture is either used as such or purified by flash chromatography on silica gel to afford the titled compound.

Illustrative synthesis of E092: methyl 1-(4-fluorophenyl)-3-isopropyl-4-[4-(methoxymethyl)-1-piperidyl]pyrazolo[3,4-b]pyridine-6-carboxylate

A mixture of HP05 (6.71 g, 19.29 mmol, 1.0 equiv), 4-(methoxymethyl)piperidine hydrochloride (CAS 916317-00-5, 6.39 g, 38.58 mmol, 2 equiv) and DIPEA (10.1 mL, 57.88 mmol, 3 equiv) in anhydrous DMSO (65 mL) was heated at 100° C. for 20 h. The reaction mixture was cooled to RT, partitioned between ethyl acetate (300 mL) and a mixture of water and a saturated solution of NaCl 1:1 (300 mL). The two phases were separated, and the aqueous phase was extracted with ethyl acetate (150 mL). The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The crude mixture was purified by flash chromatography on silica gel eluting with n-heptane/ethyl acetate to afford the titled compound.

Method I4: Chan-Lam Coupling

To a solution of ethyl 1H-pyrazolo[3,4-b]pyridine-6-carboxylate intermediate (1.0 equiv) in dichloromethane at RT is added the aryl boronic acid (2.0 to 3.0 equiv), copper(II) acetate (CAS 142-71-2, 1.5 equiv) and pyridine (4.0 equiv). The reaction mixture is stirred at room temperature under air for 1 h to 48 h. Then the reaction mixture is filtered on a pad of diatomaceous earth. Solids are washed with dichloromethane, and the filtrate is concentrated in vacuo. The resulting residue is purified by flash chromatography on silica gel to afford the titled compound.

Illustrative synthesis of E111: ethyl 1-(2-fluoro-4-pyridyl)-3-isopropyl-4-(4-methoxy-1-piperidyl)pyrazolo[3, 4-b]pyridine-6-carboxylate

To a solution of ethyl 3-isopropyl-4-(4-methoxy-1-piperidyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (E109, 70 mg, 0.20 mmol, 1.0 equiv) in dichloromethane (2 mL) at RT was added (2-fluoropyridin-4-yl)boronic acid (CAS: 401815-98-3, 56 mg, 0.40 mmol, 2.0 equiv), copper(II) acetate (CAS 142-71-2, 54 mg, 0.30 mmol, 1.5 equiv) and pyridine (64 μL, 0.80 mmol, 4.0 equiv). The reaction mixture was stirred at room temperature under air overnight. The reaction mixture was filtered on a pad of diatomaceous earth. Solids were washed with dichloromethane, and the filtrate was concentrated in vacuo. The resulting residue was purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate: 100/0 to 70/30) to give the titled compound.

Method I5: Nucleophilic Substitution

-   A is CH or N -   LG¹ and LG² are independently F, Cl or Br

To a solution of ethyl 1H-pyrazolo[3,4-b]pyridine-6-carboxylate intermediate (1.0 equiv) in anhydrous DMF or THF under nitrogen atmosphere at 0° C. is added sodium hydride (60% in mineral oil, from 1.2 equiv to 1.5 equiv), and the mixture is stirred 5 minutes at 0° C. Then an aromatic halide (2.0 equiv) is added, and the reaction mixture is warmed up to RT and stirred overnight. The reaction mixture is partitioned between water and ethyl acetate and acidified to pH 5 with AcOH. The two phases are separated. The organic phase is washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the titled compound which is used as such or purified by flash chromatography on silica gel.

Illustrative synthesis of E133: ethyl 1-(6-bromo-2-pyridyl)-3-isopropyl-4-(4-methoxy-1-piperidyl)pyrazolo[3, 4-b]pyridine-6-carboxylate

To a solution of ethyl 3-isopropyl-4-(4-methoxy-1-piperidyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (E109, 245 mg, 0.71 mmol, 1.0 equiv) in anhydrous DMF (3 mL) under nitrogen atmosphere at 0° C. was added sodium hydride (60% in mineral oil, 34 mg, 0.85 mmol, 1.2 equiv), and the mixture was stirred 5 minutes at 0° C. Then 2-bromo-6-fluoropyridine (CAS 144100-07-2, 250 mg, 1.42 mmol, 2.0 equiv) was added, and the reaction mixture was warmed up to RT and stirred overnight. The reaction mixture was partitioned between water and ethyl acetate and acidified to pH 5 with AcOH. The two phases were separated. The organic phase was washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the titled compound which was used as such.

Method I6: Alkylation

To a suspension of ethyl 3-isopropyl-4-[4-(methoxymethyl)-1-piperidyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate E148 (1.0 equiv) in anhydrous DMF under nitrogen atmosphere is added potassium carbonate (1.2 equiv), then alkyl bromide (1.1 equiv). The reaction mixture is stirred at room temperature overnight. Then cesium carbonate (1.2 equiv) and potassium iodide (0.1 equiv) are added, and the reaction mixture is stirred at room temperature for 24 h. The mixture is partitioned between water and ethyl acetate. The aqueous phase is extracted with ethyl acetate. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The crude mixture is purified by flash chromatography on silica gel to afford the titled compound.

Illustrative synthesis of E154: ethyl 1-(cyclobutylmethyl)-3-isopropyl-4-[4-(methoxymethyl)-1-piperidyl]pyrazolo[3,4-b]pyridine-6-carboxylate

To a suspension of ethyl 3-isopropyl-4-[4-(methoxymethyl)-1-piperidyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate E148 (100 mg, 0.28 mmol, 1.0 equiv) in anhydrous DMF (2 mL) under nitrogen atmosphere was added potassium carbonate (47 mg, 0.34 mmol, 1.2 equiv) and then (bromomethyl)cyclobutane (CAS: 17247-58-4, 35 μL, 0.31 mmol, 1.1 equiv). The reaction mixture was stirred at room temperature overnight. Then cesium carbonate (111 mg, 0.34 mmol, 1.2 equiv) and potassium iodide (5 mg, 0.028 mmol, 0.1 equiv) were added, and the reaction mixture was stirred at room temperature for 24 h. The mixture was partitioned between water and ethyl acetate. The aqueous phase was extracted with ethyl acetate. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The crude mixture was purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate gradient from 100/0 to 75/25) to afford the titled compound.

Method I7: Buchwald Coupling Illustrative synthesis of E157: ethyl 3-isopropyl-4-[4-(methoxymethyl)-1-piperidyl]-1-(1-methyl-6-oxo-pyridazin-3-yl)pyrazolo[3,4-b]pyridine-6-carboxylate

A suspension of ethyl 3-isopropyl-4-[4-(methoxymethyl)-1-piperidyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate E148 (100 mg, 0.28 mmol, 1.0 equiv) in anhydrous toluene (1 mL) was degassed with nitrogen (bubbling) at room temperature for 5 minutes. Then to this suspension was added 6-bromo-2-methyl-pyridazin-3-one (CAS 1123169-25-4, 58 mg, 0.31 mmol, 1.1 equiv), cesium carbonate (365 mg, 1.12 mmol, 4.0 equiv), Xantphos (CAS 161265-03-8, 16 mg, 0.028 mmol, 0.1 equiv), and palladium(II) acetate (CAS 3375-31-3, 3 mg, 0.014 mmol, 0.05 equiv). The mixture was purged again with nitrogen at RT for 10 minutes, and then the mixture was stirred at reflux overnight. The reaction mixture was cooled down and concentrated in vacuo. The residue was partitioned between water and ethyl acetate. The aqueous phase was extracted with ethyl acetate. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The crude mixture was purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate gradient from 100/0 to 0/100) to afford the titled compound.

Method I8: Buchwald Coupling

A suspension of aryl bromide intermediate (1.0 equiv), XPhos Pd G1 (CAS 1028206-56-5, 0.1 equiv) and sodium tert-butoxide (CAS: 865-48-5, 1.3 equiv) in anhydrous toluene is degassed with argon (bubbling) at room temperature for 15 minutes. Amine (1.3 equiv) is added, and the mixture is purged with argon at RT for 2 minutes. The reaction mixture is stirred at 100° C. for 30 minutes to 24 h. The reaction mixture is concentrated in vacuo, and the residue is partitioned between water and dichloromethane and filtered on a pad of Celpure P65®. Solids were washed with dichloromethane and water, and the two phases of the filtrate are separated. The aqueous layer is extracted with dichloromethane. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The titled compound is obtained from the crude mixture either by precipitation or by purification by flash chromatography on silica gel.

Illustrative synthesis of E002: ethyl 1-[3-(azetidin-1-yl)phenyl]-3-isopropyl-4-(4-morpholinophenyl)pyrazolo[3, 4-b]pyridine-6-carboxylate

A suspension of ethyl 1-(3-bromophenyl)-3-isopropyl-4-(4-morpholinophenyl)pyrazolo[3,4-b]pyridine-6-carboxylate E001 (60 mg, 0.115 mmol, 1.0 equiv), XPhos Pd G1 (CAS 1028206-56-5, 9 mg, 0.011 mmol, 0.1 equiv), and sodium tert-butoxide (CAS: 865-48-5, 14 mg, 0.149 mmol, 1.3 equiv) in anhydrous toluene (1.2 mL) was degassed with argon (bubbling) at room temperature for 15 minutes. Azetidine (13 μL, 0.149 mmol, 1.3 equiv) was added, and the mixture was purged with argon at RT for 2 minutes. The reaction mixture was stirred at 100° C. for 1 hour. The reaction mixture was concentrated in vacuo; the residue was partitioned between water and dichloromethane, and then was filtered on a pad of Celpure P65®. Solids were washed with dichloromethane and water, and the two phases of the filtrate were separated. The aqueous layer was extracted with dichloromethane. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The residue was purified by flash chromatography on silica gel (eluent system: dichloromethane/methanol gradient from 100/0 to 90/10). The obtained solid was suspended in ethanol, filtered, washed with diethyl ether and dried in vacuo to afford the titled compound.

Method I9: Esterification

To the acid (1 equiv) in either ethanol or methanol at RT is added concentrated sulfuric acid (catalytic amount). The reaction mixture is refluxed for 1 h to several days (up to 8 days). Then the reaction mixture is cooled down to RT. The resulting suspension is filtered; the solid is washed with either ethanol or methanol and then dried in vacuo. The crude solid is purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate) to give the titled compound.

Alternatively, if no suspension is formed when cooling down the reaction mixture, the solvent is removed in vacuo. The resulting residue is taken up in dichloromethane and basified with a saturated solution of NaHCO₃. The two phases are separated, and the aqueous phase is extracted with dichloromethane. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the titled compound which is used as such or further purified by flash chromatography on silica gel.

Illustrative synthesis of E001 ethyl 1-(3-bromophenyl)-3-isopropyl-4-(4-morpholinophenyl)pyrazolo[3,4-b]pyridine-6-carboxylate

Concentrated sulfuric acid (0.23 mL) was added to a suspension of A117 (2.56 g, 4.9 mmol) in absolute ethanol (64 mL) at RT. The reaction mixture was refluxed for 5 hours. The reaction mixture was cooled down to RT, and the obtained suspension was filtered. The cake was washed with ethanol and dried in vacuo. The solid residue was purified by chromatography on silica gel (heptane/ethyl acetate 100/0 to 70/30) to give the titled compound.

Method I10: Buchwald Coupling on the Aryl Linker

To the amine (from 1.3 to 2 equiv), E010 (1 equiv) and sodium tert-butoxide (CAS: 865-48-5, from 1.3 to 3 equiv) is added degassed anhydrous toluene. The reaction mixture is purged with argon, XPhos Pd G1 (CAS 1028206-56-5, 0.1 equiv) is added, and the mixture is purged again with argon. The reaction mixture is stirred at a temperature ranging from 90° C. to 110° C. for 1 h to 24 h. The reaction mixture is cooled down and filtered on a pad of diatomaceous earth. Solids are washed with organic solvents, and the combined filtrates are concentrated in vacuo. The resulting residue is purified by flash chromatography on silica gel to afford the titled compound.

Illustrative synthesis of E011: ethyl 4-[4-[3-(dimethylamino)azetidin-1-yl]phenyl]-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

To N,N-imethylazetidin-3-amine hydrochloride (CAS: 935670-07-8, 40 mg, 0.194 mmol, 1.3 equiv), E010 (100 mg, 0.23 mmol, 1 equiv) and sodium tert-butoxide (CAS: 865-48-5, 57 mg, 0.598 mmol, 2.6 equiv) was added degassed toluene (2 mL). The reaction mixture was purged with argon, XPhos Pd G1 (CAS 1028206-56-5, 17 mg, 0.023 mmol, 0.1 equiv) was added and the mixture was purged again with argon. The reaction mixture was stirred at 100° C. for 1 hour. The reaction mixture was cooled down and filtered on a pad of diatomaceous earth. Solids were washed with toluene, ethyl acetate and dichloromethane, and the combined filtrates were concentrated in vacuo. The residue was purified by flash chromatography on silica gel (dichloromethane/methanol 98/2) to afford the titled compound.

Method I11A: Sulfonyl Derivatives

A solution of amine (1 equiv) and triethyl amine (3.3 equiv) in DCM is cooled in an ice bath and a sulfonyl chloride derivative (1.1 equiv) is added. The reaction mixture is stirred at a temperature ranging from 0° C. to RT until complete conversion. The organic phase is diluted with DCM, washed with a saturated aqueous solution of NaHCO₃ and a saturated aqueous solution of NaCl. The organic phase is dried over sodium sulfate, filtered and concentrated under reduced pressure. The crude sample can be purified by flash column chromatography to give the titled compound or used as such in the next step.

Illustrative synthesis of E201: ethyl 3-methyl-4-[4-(4-methylsulfonylpiperazin-1-yl)phenyl]-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

A solution of E324 (44 mg, 0.1 mmol) and triethyl amine (46 μL, 0.33 mmol) in DCM (0.5 mL) was cooled in an ice bath, and methanesulfonyl chloride (9 μL, 0.11 mmol) was added. The reaction mixture was stirred for 20 minutes in an ice bath and then left warming to RT for 2 hours. The organic phase was diluted with DCM (10 mL) and washed successively with a saturated aqueous solution of NaHCO₃ and a saturated aqueous solution of NaCl. The organic phase was dried over sodium sulfate, filtered and concentrated under reduced pressure. The crude sample was purified by flash column chromatography eluting with a gradient of DCM and methanol to give the titled.

Method H1B: Acylation

Acetyl chloride (2 equiv) is added at RT to a solution of amine (1 equiv) and triethylamine (2 equiv) in DCM. The solution is stirred until conversion was obtained. The organic phase is diluted with DCM, washed with a saturated aqueous solution of NaHCO₃ and a saturated aqueous solution of NaCl. The organic phase is dried over sodium sulfate, filtered and concentrated under reduced pressure. The crude sample can be purified by flash column chromatography to give the titled compound or used as such in the next step.

Illustrative synthesis of E204: ethyl 1-(1-acetyl-4-piperidyl)-3-isopropyl-4-(4-morpholinophenyl)pyrazolo[3,4-b]pyridine-6-carboxylate

Acetyl chloride (21 μL, 0.3 mmol) was added at RT to a solution of E325 (70 mg, 0.15 mmol) and triethyl amine (21 μL, 0.3 mmol) in DCM (1.5 mL). The solution was stirred for 3 hours. The solution was diluted with DCM, washed with a saturated aqueous solution of NaHCO₃ and a saturated aqueous solution of NaCl. The organic phase was dried over sodium sulfate, filtered and concentrated under reduced pressure. The crude sample was purified by flash column chromatography eluting with a gradient of DCM and methanol to give the titled compound.

Synthesis of E176: methyl 4-[(1-acetyl-4-piperidyl)methoxy]-1-(4-fluorophenyl)-3-isopropyl-pyrazolo[3,4-b]pyridine-6-carboxylate

To E177 (0.1 g, 0.23 mmol, 1 equiv) in anhydrous dichloromethane (2 mL) at RT was added acetyl chloride (CAS 75-36-5, 19 μL, 0.28 mmol, 1.2 equiv) followed by triethylamine (47 μL, 0.345 mmol, 1.5 equiv). The reaction mixture was stirred at RT for 2 h. The reaction mixture was diluted with dichloromethane and water. The two phases were separated, and the aqueous phase was extracted with dichloromethane. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue was purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate gradient from 100/0 to 0/100) to afford the titled compound.

Synthesis of E178: methyl 1-(4-fluorophenyl)-3-isopropyl-4-[(1-methoxycarbonyl-4-piperidyl)methoxy]pyrazolo[3, 4-b]pyridine-6-carboxylate

To E177 (0.1 g, 0.23 mmol, 1 equiv) in anhydrous dichloromethane (2 mL) at RT was added methyl chloroformate (CAS: 79-22-1, 19 μL, 0.28 mmol, 1.2 equiv) followed by triethylamine (47 μL, 0.345 mmol, 1.5 equiv). The reaction mixture was stirred at RT for 2 h. The reaction mixture was diluted with dichloromethane and water. The two phases were separated, and the aqueous phase was extracted with dichloromethane. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue was purified by flash chromatography on silica gel (eluent system: heptane/ethyl acetate gradient from 100/0 to 50/50) to afford the titled compound.

Synthesis of E042: ethyl 4-(4-acetamidophenyl)-1-(3,5-difluorophenyl)-3-(1-methoxycarbonylazetidin-3-yl)pyrazolo[3,4-b]pyridine-6-carboxylate

Diisopropylethylamine (0.045 mL, 0.26 mmol, 2.0 equiv) and 4-(dimethylamino)pyridine (CAS 1122-58-3, 3 mg, 0.026, 0.2 equiv) were added to a solution of E043 (65 mg, 0.13 mmol, 1 equiv) in dichloromethane (1 mL) at RT. The reaction mixture was cooled to 0° C. and methyl chloroformate (CAS: 79-22-1, 0.010 mL, 0.13 mmol, 1.0 equiv) was added. The reaction mixture was stirred at RT for 45 min then partitioned between dichloromethane and water. The organic phase was separated, washed with water, dried over MgSO₄, filtered and concentrated. The residue was purified by silica gel chromatography (DCM/MeOH: 100/0 to 93/7) to give the titled compound.

Synthesis of E129: methyl 3-cyclobutyl-4-(1-methoxycarbonyl-3,3a,4,6,7,7a-hexahydro-2H-pyrrolo[3,2-c]pyridin-5-yl)-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

To E130 (31 mg, 0.073 mmol, 1 equiv) in anhydrous dichloromethane (0.5 mL) at 0° C. was added triethylamine (31 μL, 0.219 mmol, 3 equiv) followed by methyl chloroformate (CAS: 79-22-1, 7 μL, 0.088 mmol, 1.2 equiv). The reaction mixture was stirred at RT for 1.5 h. The reaction mixture was diluted with dichloromethane and water. The two phases were separated, and the aqueous phase was extracted with dichloromethane. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue was purified by flash chromatography on silica gel (eluent system: dichloromethane/methanol, gradient from 100/0 to 98/2) to afford the titled compound.

Synthesis of E132: methyl 4-(1-acetyl-3,3a,4,6,7,7a-hexahydro-2H-pyrrolo[3,2-c]pyridin-5-yl)-3-cyclobutyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

To E130 (31 mg, 0.073 mmol, 1 equiv) in anhydrous dichloromethane (2 mL) at 0° C. was added (31 μL, 0.219 mmol, 3 equiv) followed by acetyl chloride (CAS 75-36-5, 5 μL, 0.088 mmol, 1.2 equiv). The reaction mixture was stirred at RT for 1.5 h. The reaction mixture was diluted with dichloromethane and water. The two phases were separated, and the aqueous phase was extracted with dichloromethane. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue was purified by flash chromatography on silica gel (eluent system: dichloromethane/methanol, gradient from 100/0 to 96/4) to afford the titled compound.

Method I12: Nucleophilic Substitution

To a solution of the intermediate ester (1.0 equiv) in anhydrous DMSO, are added the amine (from 2.0 to 3.0 equiv) and K₂CO₃ (3.0 equiv). The reaction mixture is stirred at 100° C. overnight. The reaction mixture is cooled down to RT, poured into water and extracted with ethyl acetate. The combined organic layers are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue is purified by silica gel chromatography to afford the titled compound.

Illustrative synthesis of E110: ethyl 3-isopropyl-4-(4-methoxy-1-piperidyl)-1-(2-pyrrolidin-1-yl-4-pyridyl)pyrazolo[3,4-b]pyridine-6-carboxylate

To a solution of ethyl 1-(2-fluoro-4-pyridyl)-3-isopropyl-4-(4-methoxy-1-piperidyl)pyrazolo[3,4-b]pyridine-6-carboxylate E111 (50 mg, 0.11 mmol, 1.0 equiv) in anhydrous DMSO (1 mL), were added pyrrolidine (18 μL, 0.22 mmol, 2.0 equiv) and K₂CO₃ (46 mg, 0.33 mmol, 3.0 equiv). The reaction mixture was stirred at 100° C. overnight. The reaction mixture was cooled down to RT, poured into water and extracted with ethyl acetate. The combined organic layers were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The crude residue was purified by silica gel chromatography (heptane/ethyl acetate: 100/0 to 40/60) to afford the titled compound.

Method I13: O-Alkylation of the Pyrazole

Intermediate E153 (1.0 equiv), the alkyl iodide (from 3 to 5.7 equiv) and cesium carbonate (from 3 to 5.7 equiv) are charged in a sealed vial. NMP is added, and the vial is sealed. The reaction mixture is stirred at 130° C. for 1 hour. The reaction mixture is cooled down to RT and partitioned between water and ethyl acetate. The phases are separated, and the aqueous phase is extracted with ethyl acetate. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the titled compound which is used as such or purified by flash chromatography on silica gel.

Illustrative synthesis of E152: ethyl 3-[(1-tert-butoxycarbonyl-4-piperidyl)oxy]-4-[6-(4-cyano-1-piperidyl)-3-pyridyl]-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

Intermediate E153 (110 mg, 0.23 mmol), N-Boc-4-iodo-piperidine (CAS: 301673-14-3, 410 mg, 1.32 mmol, 5.7 equiv) and cesium carbonate (430 mg, 1.32 mmol, 5.7 equiv) were charged in a sealed vial. NMP (2.9 mL) was added, and the vial was sealed. The reaction mixture was stirred at 130° C. for 1 hour. The reaction mixture was cooled down to RT and partitioned between water and ethyl acetate. The phases were separated, and the aqueous phase was extracted with ethyl acetate. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The residue was purified by silica gel chromatography (heptane/ethyl acetate: gradient from 100/0 to 2:1) to give the titled compound.

Method I14: Mitsunobu Reaction

Diisopropyl azodicarboxylate (CAS: 2446-83-5, 0.606 mL, 3.075 mmol, 1.5 equiv) is added dropwise to a stirred solution of the intermediate phenol HP (1 equiv), tetrahydropyran-4-methanol (CAS: 14774-37-9, from 1.5 to 2.0 equiv) and triphenylphosphine (CAS: 603-35-0, 1.5 equiv) in tetrahydrofuran under nitrogen atmosphere. The reaction mixture is stirred at RT for 1 to 3 h. The solvent is removed under reduced pressure, and the resulting crude sample is purified by flash column chromatography on silica gel (eluent system: heptane/ethyl acetate) to yield the titled compound.

Illustrative synthesis of E183 ethyl 1-[(2,4-dimethoxyphenyl)methyl]-3-isopropyl-4-(tetrahydropyran-4-ylmethoxy)pyrazolo[3,4-b]pyridine-6-carboxylate

Diisopropyl azodicarboxylate (CAS: 2446-83-5, 0.606 mL, 3.075 mmol, 1.5 equiv) was added dropwise to a stirred solution of HP06 (820 mg, 2.05 mmol), tetrahydropyran-4-methanol (CAS: 14774-37-9, 477 mg, 4.1 mmol, 2.0 equiv) and triphenylphosphine (CAS: 603-35-0, 806 mg, 3.075 mmol, 1.5 equiv) in tetrahydrofuran (20 mL) under nitrogen atmosphere. The reaction mixture was stirred at RT for 1 hour. The solvent was removed under reduced pressure, and the crude sample was purified by flash column chromatography on silica gel eluting with n-heptane/ethyl acetate from 90/10 to 1/1 to yield the titled compound.

Method I15: Dimethoxybenzyl Group Removal

Trifluoroacetic acid or a mixture of dichloromethane and trifluoroacetic acid is added to the (2,4-dimethoxyphenyl)methyl]pyrazolo[3,4-b]pyridine compound. The reaction mixture is stirred at RT for several hours. Then the titled compound is isolated by precipitation in diethyl ether directly from the reaction mixture or after removal of volatiles and is used as such or is taken up in dichloromethane and basified with a saturated solution of sodium hydrogencarbonate. The phases are separated and the aqueous phase is extracted with dichloromethane. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the titled compound which is used as such or further purified by silica gel chromatography.

Alternatively the reaction mixture is concentrated in vacuo. The residue is taken up in dichloromethane and basified with a saturated solution of sodium hydrogencarbonate. The phases are separated and the aqueous phase is extracted with dichloromethane. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo which was used as such or purified by precipitation or by flash chromatography on silica gel.

Illustrative synthesis of compound E055: ethyl 3-isopropyl-4-(4-morpholinophenyl)-1H-pyrazolo[3, 4-b]pyridine-6-carboxylate

Trifluoroacetic acid (4.24 mL, 55.4 mmol, 71 equiv) was added to compound E056 (424 mg, 0.78 mmol). The reaction mixture was stirred at RT for 3 hours. Diethyl ether (20 mL) was added to the reaction mixture which was vigorously stirred for 5 minutes. The resulting suspension was filtered, and the cake was washed with diethyl ether. The solid was partitioned between dichloromethane and a saturated solution of sodium hydrogencarbonate and vigorously stirred. The suspension was filtered, and the solids were washed with dichloromethane. The two phases of the filtrate were separated, and the aqueous phase was extracted with dichloromethane. The combined organic phases were dried over MgSO₄, filtered and concentrated in vacuo to yield the titled compound which was used without further purification.

Method I16: Ullmann Coupling Synthesis of E171: ethyl 3-cyclobutyl-1-(4-fluorophenyl)-4-(tetrahydropyran-4-ylmethoxy)pyrazolo[3, 4-b]pyridine-6-carboxylate

A degassed solution of trans-N,N′-dimethyl-1,2-cyclohexane (CAS: 67579-81-1, 0.002 mL, 0.01 mmol, 0.15 equiv) and 1-fluoro-4-iodobenzene (CAS: 352-34-1, 0.007 mL, 0.06 mmol, 0.7 equiv) in toluene (2 mL) was added to a mixture of E172 (30 mg, 0.08 mmol), K₃PO₄ (35 mg, 0.167 mmol, 2.0 equiv) and CuI (1 mg, 0.005 mmol, 0.07 equiv). The vial was sealed and the reaction mixture was stirred at 110° C. for 16 hours. The reaction mixture was cooled down to RT and partitioned between water and ethyl acetate. The organic phase was separated, dried over MgSO₄, filtered and concentrated in vacuo. The residue was purified by silica gel chromatography (dichloromethane/heptane/ethyl acetate: 100/0/0 to 0/70/30) to give the titled compound.

Method I17: O-Alkylation of Pyrazole Synthesis of compound E090: isopropyl 3-isopropoxy-4-(4-morpholinophenyl)-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

To a solution of AI15 (330 mg, 0.79 mmol) and 2-iodopropane (CAS 75-30-9, 0.19 mL, 1.90 mmol, 2.4 equiv) in anhydrous NMP (4 mL) was added cesium carbonate (775 mg, 2.38 mmol, 3.0 equiv), and the reaction mixture was stirred at 130° C. for 16 hours. The reaction mixture was cooled down to RT and partitioned between dichloromethane and a saturated solution of sodium hydrogencarbonate. The organic phase was separated, washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The residue was purified by silica gel chromatography (petroleum ether/ethyl acetate: 80/20 to 70/30) to give the titled compound.

Synthesis of intermediate E506: methyl 4-(4-bromophenyl)-1-cyclohexyl-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

To a solution containing methyl 4-(4-bromophenyl)-1-cyclohexyl-3-hydroxy-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (30.5 mmol, E505) was added isopropyl bromide ([75-26-3], 5.73 mL, 61.1 mmol) and Cs₂CO₃ (2.70 g, 8.28 mmol), and the resulting mixture stirred under N₂ at 60° C. for 1 hour. The mixture was diluted with water and extracted with ethyl acetate. The organic phase was washed with brine ((2×)) and concentrated. The obtained residue was purified by column chromatography using a petroleum ether/EtOAc gradient (95/5 till 90/10) to afford the titled compound.

Synthesis of intermediate E507: methyl 4-(4-bromophenyl)-3-(cyclobutyloxy)-1-cyclohexyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

To a solution containing methyl 4-(4-bromophenyl)-1-cyclohexyl-3-hydroxy-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (5.52 mmol, E505) was added cyclobutyl bromide ([4399-47-7], 1.04 mL, 11.0 mmol) and Cs₂CO₃ (5.40 g, 11.0 mmol), and the resulting mixture stirred under N₂ at 60° C. for 1 hour. The mixture was diluted with water and extracted with ethyl acetate. The organic phase was washed with brine ((2×)) and concentrated. The obtained residue was purified by column chromatography using a petroleum ether/EtOAc gradient (95/5 till 90/10) to afford the titled compound.

Method I18: Alkylation

An amine (1 equiv) is alkylated with a halogenated alkyl derivative (1.2 to 1.5 equiv) and potassium carbonate (3 equiv) in DMF at RT or at 100° C. for 20 hours. The reaction mixture is diluted with ethyl acetate and washed with water and/or a saturated aqueous solution of NaHCO₃ and/or a saturated aqueous solution of NaCl. The organic phase is dried over sodium sulfate, filtered and concentrated under reduced pressure. The crude sample is purified by flash column chromatography to give the titled compound.

Illustrative synthesis of E208: ethyl 1-[1-(cyanomethyl)-4-piperidyl]-3-isopropyl-4-(4-morpholinophenyl)pyrazolo[3,4-b]pyridine-6-carboxylate

A suspension of E325 (70 mg, 0.15 mmol), bromoacetonitrile (12 μL, 0.17 mmol) and potassium carbonate (61 mg, 0.44 mmol) in DMF (1 mL) was stirred at RT for 20 hours. The reaction mixture was diluted with ethyl acetate and washed successively with water, a saturated aqueous solution of NaHCO₃ and a saturated aqueous solution of NaCl. The organic phase was dried over sodium sulfate, filtered and concentrated under reduced pressure. The crude sample was purified by flash column chromatography eluting with a gradient of DCM and methanol to give the titled compound.

Illustrative synthesis of E210: ethyl 4-[4-[4-(cyanomethyl)piperazin-1-yl]phenyl]-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

A suspension of E324 (70 mg, 0.15 mmol), bromoacetonitrile (16 μL, 0.24 mmol) and potassium carbonate (65 mg, 0.47 mmol) in DMF (2 mL) was stirred at 80° C. for 20 hours. The reaction mixture was cooled down to RT, diluted with ethyl acetate and washed with water. The organic phase was dried over sodium sulfate, filtered and concentrated under reduced pressure. The crude sample was purified by flash column chromatography eluting with a gradient of ethyl acetate and n-heptane to give the titled compound.

Method I19: NaH Alkylation

To a solution of the corresponding amine (1.0 equiv) in anhydrous DMF under a nitrogen atmosphere at 0° C. is added sodium hydride (1.5 equiv). The resulting solution is stirred at 0° C. or at room temperature for 5 to 30 min, and then methyl iodide (1.5 equiv) is added. The reaction mixture is stirred at room temperature or heated to 55° C. until completion. The mixture is then quenched by addition of water, and extracted with EtOAc. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The crude residue is purified by silica gel chromatography or by preparative HPLC.

Illustrative synthesis of intermediate E218: methyl 4-[4-[cyclobutyl(methyl)amino]phenyl]-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

To a solution of E337 (21 mg, 0.049 mmol, 1.0 equiv) in anhydrous DMF (4.4 mL) under a nitrogen atmosphere was added sodium hydride (60% in oil, 3 mg, 0.074 mmol, 1.5 equiv). The resulting solution was stirred at 55° C. for 3 min, and then methyl iodide (4.6 μL, 0.074 mmol, 1.5 equiv) was added. The reaction mixture was stirred at 55° C. for 5 min, and then at room temperature overnight. The mixture was quenched by addition of water and extracted with EtOAc. The combined organic phases were washed with a saturated NaHCO₃ solution and brine, dried over Na₂SO₄, filtered and concentrated in vacuo. The crude residue was finally purified by silica gel chromatography (heptane/EtOAc: 100/0 to 65/35) to afford the titled compound.

Method I20: Deprotection of Amine by Hydrogenolysis

A suspension of the corresponding ester (1.0 equiv) and Pd/C (10%) in THF/EtOH is hydrogenated until completion. The reaction mixture is filtered over Celpure® and washed with DCM and MeOH, and the filtrate is concentrated in vacuo. The crude residue is then used directly in the next step or purified by silica gel chromatography or preparative HPLC.

Illustrative synthesis of intermediate E328: ethyl 3-isopropyl-4-(4-morpholinophenyl)-1-pyrrolidin-3-yl-pyrazolo[3,4-b]pyridine-6-carboxylate

A suspension of ester E340 (180 mg, 0.30 mmol, 1.0 equiv) and Pd/C (10%, 18 mg) in THF/EtOH (2 mL/1 mL) was hydrogenated overnight. The reaction mixture was filtered over Celpure® and washed with DCM and EOH, and the filtrate was concentrated in vacuo to afford the titled compound.

Method I21: Tert-Butoxy Carbonyl (Boc) Deprotection Method I21A: Trifluoroacetic Acid Treatment

Trifluoroacetic acid (from 30 to 33 equiv) is added to a solution of tert-butoxycarbonyl protected compound (1 equiv) in DCM. The solution is stirred at RT until complete deprotection. The reaction mixture is diluted with DCM and washed with a saturated aqueous solution of NaHCO₃. The organic phase is dried over sodium sulfate, filtered and concentrated in vacuo to give the titled compound.

Illustrative synthesis of E327: ethyl 3-methyl-1-phenyl-4-(4-piperidyl)pyrazolo[3,4-b]pyridine-6-carboxylate

Trifluoroacetic acid (470 μL, 6.1 mmol) was added to a solution of E339 (95 mg, 0.2 mmol) in DCM (5 mL). The solution was stirred at RT for 1.5 hours. The reaction mixture was diluted with DCM (30 mL) and washed with a saturated aqueous solution of NaHCO₃. The organic phase was dried over sodium sulfate, filtered and concentrated in vacuo to give the titled compound.

Method I21B: Hydrochloric Acid Treatment

The tert-butoxycarbonyl-protected compound (1 equiv) is dissolved in dioxane. 4 M HCl in dioxane (from 4 equiv to 8 equiv) is added, and the solution was stirred at RT until complete deprotection. The solvent is concentrated under reduced pressure to give the titled compound. The solution can also be worked up by dilution with DCM and washing with a saturated aqueous solution of NaHCO₃. The organic phase is separated using a phase separator and concentrated under reduced pressure. The titled compound is used as such in the next step without any further purification.

Illustrative synthesis of E332: ethyl 4-(2,3,3a,4,6,6a-hexahydro-1H-pyrrolo[3,4-c]pyrrol-5-yl)-3-isopropyl-1-(m-tolyl)pyrazolo[3, 4-b]pyridine-6-carboxylate

E264 (58 mg, 0.11 mmol) was dissolved in dioxane (2 mL). 4 M HCl in dioxane (110 μL, 0.44 mmol) was added, and the solution was stirred at RT for 18 hours. The reaction mixture was diluted with DCM and washed with a saturated aqueous solution of NaHCO₃. The organic phase is separated using a phase separator and concentrated under reduced pressure. The titled compound is used as such in the next step without any further purification.

Method I22: Buchwald Coupling

To the amine or amide (from 1 to 1.2 equiv), the halogenated scaffold (1 equiv) and cesium carbonate (1.5 equiv) is added degassed dioxane. The reaction mixture is purged with argon, tris(dibenzylideneacetone)dipalladium(O) (CAS: 51364-51-3, 0.05 equiv) or palladium(II) acetate (0.05 equiv) and Xantphos (CAS: 161265-03-8, from 0.75 to 0.2 equiv) are added, and the mixture is purged again with argon. The reaction mixture is stirred at a temperature ranging from 100° C. to 110° C. for 30 minutes to 1.5 hours. The reaction mixture is cooled down and filtered over a diatomaceous earth pad. Solids are washed with organic solvents, and the combined filtrates are concentrated in vacuo. Alternatively the crude sample can be poured into water and extracted with ethyl acetate. The organic phase is washed with a saturated aqueous solution of NaCl, dried over sodium sulfate and concentrated under reduced pressure. The resulting residue is purified by flash chromatography on silica gel to afford the coupled compound.

Illustrative synthesis of intermediate E322: methyl 1-(4-fluorophenyl)-3-isopropyl-4-(tetrahydropyran-4-carbonylamino)pyrazolo[3,4-b]pyridine-6-carboxylate

To tetrahydropyran-4-carboxamide (CAS 344329-76-6, 45 mg, 0.34 mmol), HP05 (100 mg, 0.29 mmol) and cesium carbonate (140 mg, 0.43 mmol) was added degassed dioxane (1 mL). The reaction mixture was purged with argon, tris(dibenzylideneacetone)dipalladium(O) (CAS: 51364-51-3, 3 mg, 0.01 mmol) and Xantphos (CAS: 161265-03-8.12 mg, 0.02 mmol)) were added, and the mixture was purged again with argon. The reaction mixture was heated at 100° C. for 30 minutes, cooled down to RT and filtered over a diatomaceous earth pad. Solids were washed with ethyl acetate, and the combined filtrates were concentrated in vacuo. The resulting residue was purified by flash column chromatography eluting with n-heptane/ethyl acetate to afford the titled compound.

Method I23: General Method for Oxidation

Dess Martin's periodinane (1 to 2 eq) is added at RT to a stirred solution of alcohol (1 eq) in dichloromethane. After 0.5 to 2 hours, the reaction mixture is diluted with dichloromethane. A solution of 20% Na₂S₂O₃ in water and a saturated aqueous solution of NaHCO₃ (1:1) is added and the stirring is continued for 30 minutes. The organic phase is separated, dried over sodium sulfate, filtered and concentrated under reduced pressure to give the titled compound. The compound can be used as such or purified by flash column chromatography.

Synthesis of compound E353: Methyl 3-cyclobutyl-1-(4-fluorophenyl)-4-(4-oxopiperidin-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Dess-Martin periodinane (4 g, 9.4 mmol) was added at RT to a stirred solution of E352 (3.6 g, 8.6 mmol) in dichloromethane (40 mL). After 30 minutes, the reaction mixture was diluted with dichloromethane (50 mL). A solution of 20% aqueous Na₂S₂O₃ and a saturated aqueous solution of NaHCO₃ (1:1, 50 mL) were added, and the stirring was continued for 30 minutes. The organic phase was separated, dried over sodium sulfate, filtered and concentrated under reduced pressure to give the titled compound.

Method I24: Coupling of Amines

EDC.HCl ([25952-538], 1.2 equiv) is added at RT to a stirring solution of carboxylic acid (1 equiv), amine (4 equiv) and 4-(dimethylamino)pyridine ([1122-58-3], 2 equiv) in dichloromethane. The reaction mixture is stirred at RT for 20 hours. The solvent is evaporated under reduced pressure. The residue is purified flash column chromatography eluting with ethyl acetate/n-heptane and/or DCM/MeOH to yield the desired compound.

Illustrative Synthesis of E439: ethyl 4-{4-[5-(tert-butoxycarbonyl)hexahydropyrrolo[3,4-c]pyrrole-2(1H)-carbonyl]phenyl}-1-cyclohexyl-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

EDC.HCl ([25952-538], 18 mg, 74 μmol) was added at RT to a stirred solution of E438 (30 mg, 62 μmol), tert-butyl hexahydropyrrolo[3,4-c]pyrrole-2(1H)-carboxylate ([141449-85-6], 52 mg, 248 μmol) and 4-(dimethylamino)pyridine ([1122-58-3], 17 mg, 124 μmol) in dichloromethane (5 mL). The reaction mixture was stirred at RT for 20 hours. The mixture was concentrated under reduced pressure. The residue was purified by flash column chromatography eluting with ethyl acetate/n-heptane to yield the titled compound.

Synthesis of E441: ethyl 1-cyclohexyl-4-{4-[3-(dimethylamino)azetidine-1-carbonyl]phenyl}-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

EDC.HCl ([25952-538], 24 mg, 125 μmol) was added at RT to a stirred solution of E438 (40 mg, 89 μmol), N,N-dimethylazetidin-3-amine hydrochloride ([935670-07-8], 49 mg, 358 triethylamine (50 μL, 358 μmol) and 4-(dimethylamino)pyridine ([1122-58-3], 24 mg, 196 μmol) in dichloromethane (15 mL). The reaction mixture was stirred at RT for 20 hours. The mixture was concentrated under reduced pressure. The residue was purified by flash column chromatography eluting with ethyl acetate/DCM/MeOH (1/0/0 to 0/8/2) to yield the titled compound.

Method I25: Tert-Butoxycarbonyl (Boc) Deprotection

To a solution of the Boc-protected amine (1 eq) in dichloromethane at 0° C., TFA (76-05-1, 7 eq) is added. The resulting mixture is stirred at room temperature overnight. After dilution with DCM, the mixture is extracted with K₂CO₃ solution. The obtained organic phase is concentrated to give the desired product that is used as such.

Method I26: Reductive Amination to Install a Cyclopropyl Group

The amine (1 eq) is mixed with (1-ethoxycyclopropoxy)trimethylsilane ([27374-25-0], 2 eq), AcOH (1.6 eq) and NaBH₃CN (1.5 eq) in a mixture of THF/MeOH (1/1). The resulting mixture is stirred overnight at 50° C. After cooling the mixture down to room temperature, the reaction is quenched by the addition of water. Next, 1 M NaOH solution is added, and the mixture is stirred for another 15 minutes. After dilution with DCM, the organic layer is separated, dried and concentrated to give the titled compound.

Illustrative synthesis of compound E465: methyl 3-cyclobutyl-4-[4-(4-cyclopropylpiperazin-1-yl)piperidin-1-yl]-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Methyl 3-cyclobutyl-1-(4-fluorophenyl)-4-[4-(piperazin-1-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (200 mg, 0.41 mmol, E496) was mixed with (1-ethoxycyclopropoxy)trimethylsilane ([27374-25-0], 163 μL, 0.81 mmol), AcOH (26 μL, 0.65 mmol) and sodium cyanoborohydride ([25895-60-7], 38 mg, 0.61 mmol) in a mixture of THF/MeOH (1/1, 1 mL). The resulting mixture was stirred overnight at 50° C. After cooling the mixture down to room temperature, the reaction was quenched by the addition of water. Next, 1 M NaOH solution was added, and the mixture was stirred for another 15 minutes. After dilution with DCM, the organic layer was separated, dried and concentrated to give the titled compound.

Method I27: Amine Alkylation

The amine (1 eq) is mixed with 1-bromo-2-methoxyethane ([6482-24-2], 1.1 eq) and K₂CO₃ (2 eq) in MeCN. The resulting mixture is heated at reflux overnight at 50° C. After cooling down, the mixture is used as such in the next step.

Method I28: Amino-Carbonylation

A is CH or N

In a Parr reactor, the arylbromide (1 eq) is mixed with an amine (2 eq), Et₃N (4 eq) and Xantphos Pd G3 (0.03 eq) in dioxane. A CO pressure of 5 bar is applied and the mixture is heated at 100° C. overnight. Concentration gives a residue that is re-dissolved in DCM. Extraction with water gives an organic phase that is concentrated to give a residue that is used as such in the next step.

Illustrative synthesis of compound E474: methyl 1-cyclohexyl-4-[4-(4-methylpiperazine-1-carbonyl)phenyl]-3-[(propan-2-yl)oxy]-1H-pyrazolo[3, 4-b]pyridine-6-carboxylate

A Parr reactor was loaded with E506 (0.50 mmol, 250 mg), 1-methylpiperazine dihydrochloride ([34352-59-5], 1.0 mmol, 173 mg) and [(4,5-bis(diphenylphosphino)-9,9-dimethylxanthene)-2-(2′-amino-1,1′-biphenyl)]palladium(II) methanesulfonate] (0.015 mmol, 14 mg). The reactor was evacuated and back-filled with N₂, Et₃N (4.0 equiv, 2.0 mmol, 279 μL) and 1,4-dioxane (dry, 8 mL/mmol, 4 mL) were added, and the reaction mixture was heated to 100° C. under a CO atmosphere (5 bar) overnight. The reaction mixture was concentrated in vacuo, and the residue was partitioned between H₂O and dichloromethane. The organic phase was dried and concentrated in vacuo to give the titled compound which was used as such in the next step.

Method I29: Alternative Buchwald Coupling on the Aryl Linker

A tube is loaded with the arylbromide (1 eq). The amine (1.2 eq) is added together with (RuPhos) palladium(II) phenethylamine chloride (1:1 MTBE solvate, 0.1 eq), NaOtBu (1.2 eq) in dioxane. The resulting suspension is put under a N₂ atmosphere and stirred at 100° C. Next, the mixture is diluted with water and acidified with a 1 N citric acid solution till pH 3-4. Extraction with DCM gives the crude product that is either used as such or purified by chromatography. During this method, it is possible that partial hydrolysis of the ester to the corresponding acid occurs.

Illustrative synthesis of compound E502: methyl 1-cyclohexyl-4-[4-(4-methylpiperazin-1-yl)phenyl]-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

A tube was loaded with the E506 (100 mg, 0.21 mmol). 1-Methylpiperazine ([109-01-3], 28 μL, 0.25 mmol) was added together with (RuPhos) palladium(II) phenethylamine chloride (1:1 MTBE solvate, 17 mg, 0.02 mmol), and NaOtBu (25 mg, 0.25 mmol) in dioxane (1 mL). The resulting suspension was put under a N₂ atmosphere and stirred at 100° C. Next, the mixture was diluted with water and acidified with a 1 N citric acid solution till pH 3-4. Extraction with DCM gave the titled compound that was used as such. Partial hydrolysis of the ester to the corresponding acid was observed.

Method I30: Alternative Reductive Amination

A solution of the amine (1 eq), the ketone (2 eq) and AcOH (1.5 eq) in DCM is cooled to 0° C. Next, sodium triacetoxyborohydride ([56553-60-7], 2 eq) is added portionwise, and the reaction is stirred overnight at ambient temperature. Subsequently, the mixture is diluted with saturated NaHCO₃ solution and extracted with DCM. The organic phase is concentrated to give the alkylated amine that is used as such or purified by chromatography.

Illustrative example of compound E469: methyl 3-cyclobutyl-1-(4-fluorophenyl)-4-[9-(oxetan-3-yl)-3,9-diazaspiro[5.5]undecan-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

A solution of the methyl 3-cyclobutyl-4-(3,9-diazaspiro[5.5]undecan-3-yl)-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (200 mg, 0.42 mmol, E500), 3-oxetanone ([6704-31-0], 54 μL, 0.84 mmol) and AcOH (36 μL) in DCM (3 mL) was cooled at 0° C. Next, sodium triacetoxyborohydride ([56553-60-7], 178 mg, 0.84 mmol) was added portion wise and the reaction was stirred overnight at ambient temperature. Subsequently, the mixture was diluted with sat. NaHCO₃ solution and extracted with DCM. The organic phase was evaporated to give the titled compound.

Method I31: Carbamate Synthesis

To a solution of the amine (1 eq) in DCM is added trimethylamine (2 eq) and then methyl chloroformate ([79-22-1], 2 eq). The mixture is stirred at RT overnight. Next, the reaction mixture is diluted with saturated NaHCO₃ solution and extracted with DCM. After concentration, the carbamate is obtained that is used as such or purified by chromatography.

Illustrative example of compound E486: methyl 3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[4-(methoxycarbonyl)piperazin-1-yl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

To a solution of the E498 (118 mg, 0.239 mmol) in DCM (1 mL) was added triethylamine (67 μL, 0.478 mmol) and then methyl chloroformate (37 μL, 0.478 mmol). The mixture was stirred at RT overnight. Next, the reaction mixture was diluted with saturated NaHCO₃ solution and extracted with DCM. After concentration, the titled compound was obtained that was used as such.

Method I32: Amide Synthesis Using Acetyl Chloride

To a solution of the amine (1 eq) in DCM is added trimethylamine (2 eq) and then acetyl chloride ([75-36-5], 2 eq). The mixture is stirred at RT overnight. Next, the reaction mixture is diluted with saturated NaHCO₃ solution extracted with DCM. After concentration, the amide is obtained that is used as such or purified by chromatography.

Illustrative example of compound E487: methyl 4-[4-(4-acetylpiperazin-1-yl)piperidin-1-yl]-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

To a solution of the E498 (118 mg, 0.239 mmol) in DCM (1 mL) was added triethylamine (67 μL, 0.478 mmol) and then acetyl chloride ([75-36-5], 0.478 mmol). The mixture was stirred at RT overnight. Next, the reaction was diluted with saturated NaHCO₃ solution and extracted with DCM. After concentration, the titled compound was obtained that was used as such.

Method I33: General Method for Reductive Amination

A suspension of ketone (1 eq), amine (1.5 to 3 eq) and triethylamine (1 to 2 eq) in dichloromethane is stirred at RT for 5 minutes. Acetic acid (1 to 2 eq) is added, and the stirring at RT is continued for 30 minutes. Sodium triacetoxyborohydride (1 to 3 eq) is then added, and the stirring is continued for 20 hours. The reaction mixture is diluted with dichloromethane and washed with a saturated aqueous solution of NaHCO₃. The organic phase is separated, dried over sodium sulfate and concentrated under reduced pressure. The crude sample is used as such or purified by flash column chromatography.

Illustrative synthesis of E354: methyl 3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[2-(methoxymethyl)morpholin-4-yl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

A suspension of E353 (0.1 g, 0.24 mmol), 2-(methoxymethyl)morpholine ([156121-15-2], 63 mg, 0.47 mmol) and triethylamine (33 μL, 0.24 mmol) in dichloromethane (2 mL) was stirred at RT for 5 minutes. Acetic acid (21 μL, 0.35 mmol) was added, and the stirring at RT was continued for 30 minutes. Sodium triacetoxyborohydride (76 mg, 0.35 mmol) was then added, and the stirring was continued for 20 hours. The reaction mixture was diluted with dichloromethane (3 mL) and washed with a saturated aqueous solution of NaHCO₃ (2 mL). The organic phase was separated using a phase separator and concentrated in vacuo to give the titled compound.

Method I34: Reductive Amination on Aldehydes

A suspension of amine hydrochloride or free base (1 to 2 equiv) and triethylamine (from 1 to 2 equiv) in 1,2-dichloroethane is stirred at RT for 10 minutes. Aldehyde (1 equiv), sodium triacetoxyborohydride (2 equiv), and acetic acid (0.6 to 4 equiv) are successively added, and the stirring at RT is continued for 20 hours. Starting reagents can be added until full conversion is observed. The reaction mixture is diluted with DCM, washed with a saturated aqueous solution of NaHCO₃ and/or a saturated aqueous solution of NH₄Cl and a phosphate buffer (pH 6.2). The organic phase is dried over sodium sulfate and concentrated under reduced pressure. The residue is used as such or purified by flash column chromatography to yield the reductively aminated compound.

Illustrative synthesis of E426: ethyl 1-cyclohexyl-4-(4-{[3-(dimethylamino)azetidin-1-yl]methyl}phenyl)-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

A suspension of 3-(dimethylamino)azetidine dihydrochloride ([124668-49-1], 17 mg, 124 μmol) and triethylamine (35 μL, 248 μmol) in 1,2-dichloroethane (2 mL) was stirred at RT for 10 minutes. Aldehyde E425 (54 mg, 124 μmol), sodium triacetoxyborohydride (53 mg, 248 μmol), and acetic acid (29 μL, 496 μmol) were successively added, and the stirring at RT was continued for 20 hours. The reaction mixture was diluted with DCM and washed with a saturated aqueous solution of NaHCO₃. The organic phase was separated, dried over sodium sulfate and concentrated under reduced pressure. The residue was used as such or purified by flash column chromatography eluted with n-heptane/ethyl acetate/DCM/MeOH (100/0/0/0/0 to 0/100/0/0 and to 0/0/90/10) to yield the titled compound.

Method I35: Suzuki with Alkyl-BF₃ Salts

-   -   LG³ is a leaving group suitable for the coupling reaction     -   G^(x) is -G^(3B) or -G^(3B)-L¹-G^(3C)

The aryl halide (1 eq) is mixed together with the alkyl-BF₃ salt (1.5 eq), Pd(dppf)Cl₂.DCM (CAS 95464-05-4, 0.05 eq) and CS₂CO₃ (3 eq) in a mixture of THF/H₂O (10/1). The mixture is put under N₂ atmosphere and heated at 80° C. overnight. Concentration, possibly followed by chromatographic purification, gives the titled compound.

Synthesis of E199: methyl 4-(4-azidophenyl)-1-[3-(dimethylamino)phenyl]-3-isopropyl-pyrazolo[3,4-b]pyridine-6-carboxylate

Intermediate E200 (0.5 g, 1.013 mmol, 1.0 equiv) and sodium azide (CAS 26628-22-8, 132 mg, 2.026 mmol, 2 equiv) were put in a sealed vial. A 2:1 mixture of ethanol and water (2 mL) was added, and the vial was purged with nitrogen. Then copper(I) iodide (CAS 7681-65-4, 20 mg, 0.101 mmol, 0.1 equiv), sodium ascorbate (CAS 134-03-2, 11 mg, 0.051 mmol, 0.05 equiv) and N,N-dimethylethylenediamine (CAS 110-70-3, 45 μL, 0.405 mmol, 0.2 equiv) were added, and the vial was sealed. The reaction mixture was heated under microwave irradiation at 80° C. for 45 minutes. Volatiles were removed in vacuo. The resulting aqueous residue was diluted with ethyl acetate. The two phases were separated, and the aqueous phase was extracted with ethyl acetate. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the titled compound which was used as such.

Synthesis of E247: ethyl 3-methyl-1-phenyl-4-(piperidine-1-carbonyl)pyrazolo[3,4-b]pyridine-6-carboxylate

To a solution of acid E330 (0.09 mmol, 30 mg, 1.0 equiv) in THF were added piperidine (11 μL, 0.11 mmol, 1.2 equiv), HATU (42 mg, 0.11 mmol, 1.2 equiv), and DIPEA (19 μL, 0.11 mmol, 1.2 equiv). The solution was stirred at room temperature for 1 h then quenched by addition of a saturated NH₄Cl solution and extracted with DCM. The combined organic phases were washed with brine, dried over Na₂SO₄, filtered and concentrated in vacuo. The crude residue was finally purified by silica gel chromatography (heptane/EtOAc: 100/0 to 70/30) to afford the titled compound.

Synthesis of E197: methyl 4-(1-tert-butoxycarbonyl-4-piperidyl)-1-(4-fluorophenyl)-3-isopropyl-pyrazolo[3,4-b]pyridine-6-carboxylate

Step 1: methyl 4-(1-tert-butoxycarbonyl-3,6-dihydro-2H-pyridin-4-yl)-1-(4-fluorophenyl)-3-isopropyl-pyrazolo[3,4-b]pyridine-6-carboxylate E198

A suspension of methyl 4-chloro-1-(4-fluorophenyl)-3-isopropyl-pyrazolo[3,4-b]pyridine-6-carboxylate HP05 (2.0 g, 5.75 mmol, 1.0 equiv), tert-butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3,6-dihydro-2H-pyridine-1-carboxylate (3.6 g, 11.5 mmol, 2.0 equiv), K₂CO₃ (2.4 g, 17.25 mmol, 3.0 equiv) and Pd(dppf)₂Cl₂ (939 mg, 1.15 mmol, 0.2 equiv) in anhydrous DMF (15 mL) was degassed with N₂ at room temperature for 2 minutes. The reaction mixture was heated at reflux overnight. The mixture was cooled to RT, and the mixture was poured into 150 mL of iced water. The aqueous phase was extracted with ethyl acetate. The organic layer was washed with brine, dried over MgSO₄, filtered and concentrated. The crude was purified by silica gel chromatography (heptane/ethyl acetate: 100/0 to 80/20) to give E198.

Step 2: methyl 4-(1-tert-butoxycarbonyl-4-piperidyl)-1-(4-fluorophenyl)-3-isopropyl-pyrazolo[3,4-b]pyridine-6-carboxylate

A suspension of E198 (2.44 g, 4.93 mmol, 1.0 equiv) and PtO₂ (1.2 g) in AcOH was hydrogenated overnight. The reaction mixture was filtered over Celpure® and washed with ethyl acetate, and the filtrate was concentrated. The residue was purified by silica gel chromatography (heptane/ethyl acetate: 100/0 to 80/20) to give the titled compound.

Synthesis of E339: ethyl 4-(1-tert-butoxycarbonyl-4-piperidyl)-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

Step 1: ethyl 4-(1-tert-butoxycarbonyl-3,6-dihydro-2H-pyridin-4-yl)-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

A suspension of HP13 (167 mg, 0.53 mmol), tert-butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3,6-dihydro-2H-pyridine-1-carboxylate (164 mg, 0.53 mmol), K₃PO₄ (225 mg, 1.06 mmol) and Pd(PPh₃)₂Cl₂ (37 mg, 0.05 mmol) in DME/EtOAc (3 mL, 2/1) was degassed with N₂ at room temperature for 2 minutes. The reaction mixture was heated at 110° C. for 2 hours and cooled down to RT. The solution was diluted with 0.1 M HCl (5 mL) and extracted twice with ethyl acetate (2×10 mL). The combined organic phases were dried over sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by flash column chromatography eluting with n-heptane/ethyl acetate to give the titled compound.

Step 2: ethyl 4-(1-tert-butoxycarbonyl-4-piperidyl)-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

A solution of the compound from Step 1 (110 mg, 0.24 mmol, 1.0 equiv) in a mixture of ethanol/ethyl acetate (25 mL, 1/1) was hydrogenated using a 10% palladium over charcoal cartridge in continuous flow an H-Cube® system (20 bars, RT, 3 hours). The volatiles were removed under reduced pressure to yield the titled compound E339.

Synthesis of E330: 6-ethoxycarbonyl-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-4-carboxylic acid

Step 1: ethyl 6-hydroxy-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-4-carboxylate

5-Amino-3-methyl-1-phenylpyrazole (CAS: 1131-18-6, 10 g, 57.7 mmol) was dissolved in AcOH (100 mL). Diethyloxalacetate sodium salt (CAS: 40876-98-0, 13.4 g, 63.5 mmol) was added, and the reaction mixture was refluxed for 1.5 hours. Diethyloxalacetate sodium salt (CAS: 40876-98-0, 1.3 g, 6.3 mmol) was again added, and the reflux was continued for another 30 minutes. The reaction mixture was cooled down to RT and poured into cold water (300 mL). The precipitate was filtered, washed with water and air dried for 20 hours to yield the titled compound.

Step 2: ethyl 3-methyl-1-phenyl-6-(trifluoromethylsulfonyloxy)pyrazolo[3,4-b]pyridine-4-carboxylate

A suspension of the compound from Step 1 (13.7 g, 46 mmol) in pyridine (4.1 mL, 50.7 mmol) and acetonitrile (200 mL) was cooled in an ice bath. Triflic anhydride (8.5 mL, 50.7 mL) was added dropwise over a 30 minutes period. The reaction mixture was left warming to RT over a 20 minutes period and water (200 mL) was added. The precipitate was filtered, washed with water and ethanol, and dried at 40° C. under reduced pressure to give the titled compound.

Step 3: ethyl 6-cyano-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-4-carboxylate

Compound from Step 2 (9.2 g, 21.4 mmol) was placed in a vial and solubilized in dry dimethylformamide (40 mL). Zinc cyanide (2.5 g, 21.4 mmol) was added, and argon was bubbled into the reaction mixture for 5 minutes. Tetrakis(triphenylphosphine)palladium(O) (2.5 g, 2.1 mmol) was added, and the vial was sealed. The reaction mixture was stirred at 100° C. for 2 hours and then was cooled to room temperature. The crude mixture was poured into water, and the precipitate was filtered. The solid was suspended in ethyl acetate and filtered again. The organic phase was washed with a saturated aqueous solution of NaCl, dried over sodium sulfate, filtered and concentrated under reduced pressure to a volume of approximately 20 mL. n-Heptane (100 mL) was added, and the precipitate was filtered, washed with n-heptane and dried to give the titled compound.

Step 4: 4-(hydroxymethyl)-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carbonitrile

Sodium borohydride (1.2 g, 31.7 mmol) was added portionwise to a suspension of the compound from Step 3 (4.9 g, 15.8 mmol) in THF (20 mL) followed by addition of ethanol (50 mL). The reaction mixture was stirred at RT for 2 hours and was quenched with a saturated aqueous solution of NH₄Cl. The aqueous phase was extracted with ethyl acetate, and the organic phase was dried over sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified over a silica gel pad eluting with DCM and n-heptane to give the titled compound.

Step 5: 4-(hydroxymethyl)-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylic acid

The compound of Step 4 (1.32 g, 5 mmol) was solubilized in dioxane (10 mL) and a 6 M HCl solution in water (20 mL) was added. The solution was refluxed for 20 hours and cooled down to RT. The precipitate was filtered and washed with ethanol. The filtrate was concentrated under reduced pressure to give the titled compound which was used as such without any further purification.

Step 6: ethyl 4-(hydroxymethyl)-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

The compound from Step 5 (1.4 g, 5 mmol) was dissolved in ethanol (60 mL) and thionyl chloride (0.6 mL, 7.5 mmol) was added. The solution was refluxed for 4 hours and then cooled to RT. The volatiles were removed under reduced pressure, and the crude sample was purified by flash column chromatography eluting with DCM and methanol to yield the titled compound.

Step 7: 6-ethoxycarbonyl-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-4-carboxylic acid

The compound from Step 6 (139 mg, 0.45 mmol) was dissolved in DCM (5 mL) and Dess-Martin's periodinane (227 mg, 0.54 mmol) was added at RT. The reaction mixture was stirred for 30 minutes. The precipitate was filtered, and the filtrate was concentrated under reduced pressure. The residue was solubilized in DMF (5 mL) and Oxone® (2×166 mg, 1.08 mmol) was added over a period of 30 minutes. The stirring at RT was continued for another 30 minutes, and water was added until a precipitate was formed. The precipitate was collected by filtration, washed with water and dried at 40° C. under reduced pressure to give the titled compound, E330.

Synthesis of E390: ethyl 3-cyclobutyl-1-[2-(3,6-dihydro-2H-pyran-4-yl)pyridin-4-yl]-4-[4-(methoxymethyl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate and E391: ethyl 3-cyclobutyl-4-[4-(methoxymethyl)piperidin-1-yl]-1-[2-(oxan-4-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Step 1: E390: ethyl 3-cyclobutyl-1-[2-(3,6-dihydro-2H-pyran-4-yl)pyridin-4-yl]-4-[4-(methoxymethyl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

In a sealed tube, a suspension of E389 (110 mg, 0.23 mmol), 3,6-dihydro-2H-pyran-4-boronic pinacol ester (72 mg, 0.34 mmol), K3PO4 (146 mg, 0.69 mmol) and Pd(Amphos)C12 ([887919-35-9], 16 mg, 23 μmol) in dioxane (3 mL) and water (0.5 mL) was degassed with N2 at room temperature for 2 minutes. The reaction mixture was heated at 100° C. for 3 hours. The mixture was cooled to RT and then concentrated under reduced pressure. The crude sample was purified by flash column chromatography eluted with ethyl acetate/n-heptane (0/1 to I/O) to give the titled compound E390.

Step 2: E391: ethyl 3-cyclobutyl-4-[4-(methoxymethyl)piperidin-1-yl]-1-[2-(oxan-4-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

A suspension of E390 (60 mg, 0.11 mmol) and palladium hydroxide on carbon (20 mg) in ethanol was hydrogenated for 6 hours. The reaction mixture was filtered over Celpure® and washed with ethyl acetate. The filtrate was concentrated in vacuo to give the titled compound E391.

Synthesis of E393: ethyl 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Trifluoromethanesulfonic acid (860 μL, 10 mmol) was added dropwise at RT to a solution of E392 (1 g, 2 mmol) in dichloromethane (10 mL). The reaction mixture was stirred for 4 hours and poured into a mixture of saturated aqueous NaHCO₃ and water (1:1, 10 mL). The aqueous phase was extracted twice with dichloromethane/isopropanol (95/5, 20 mL). The combined organic phases were combined, dried over sodium sulfate, filtered and concentrated under reduced pressure to give the titled compound as a colorless solid.

Synthesis of E402: ethyl 3-cyclobutyl-1-(2-hydroxypyridin-4-yl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

A suspension of E401 (75 mg, 0.12 mmol) and palladium hydroxide on carbon (10 mg) in THF was hydrogenated for 20 hours. The reaction mixture was filtered over Celpure® that was washed with dichloromethane/methanol. The filtrate was concentrated in vacuo to give the titled compound E402.

Synthesis of E407: ethyl 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-[2-(oxan-4-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Step 1: ethyl 3-cyclobutyl-1-[2-(3,6-dihydro-2H-pyran-4-yl)pyridin-4-yl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

In a sealed tube, a suspension of E406 (110 mg, 0.21 mmol), 3,6-dihydro-2H-pyran-4-boronic pinacol ester (72 mg, 0.34 mmol), K₃PO₄ (146 mg, 0.69 mmol) and Pd(Amphos)Cl₂ ([887919-35-9], 16 mg, 23 μmol) in dioxane (3 mL) and water (0.5 mL) was degassed with N₂ at room temperature for 2 minutes. The reaction mixture was heated at 100° C. for 20 hours. The mixture was cooled to RT, and the mixture was concentrated under reduced pressure. The crude sample was purified by flash column chromatography eluted with n-heptane/ethyl acetate/DCM/MeOH (1/0/0/0 to 40/40/10/1) to give the titled compound.

Step 2: ethyl 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-[2-(oxan-4-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

A suspension of ethyl 3-cyclobutyl-1-[2-(3,6-dihydro-2H-pyran-4-yl)pyridin-4-yl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (54 mg, 0.94 mmol) and palladium hydroxide on carbon (15 mg) in ethanol/THF (1:1, 10 mL) was hydrogenated for 6 hours. The reaction mixture was filtered over Celpure® that was washed with ethyl acetate, and the filtrate was concentrated in vacuo. The residue was purified by silica gel chromatography eluted with n-heptane/ethyl acetate/DCM/MeOH (100/0/0/0/0 to 0/100/0/0 and to 0/0/90/10) to give the titled compound E407.

Synthesis of E413: methyl 3-cyclobutyl-1-(4-fluorophenyl)-4-(piperidin-4-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Step 1: methyl 4-[1-(tert-butoxycarbonyl)-1,2,3,6-tetrahydropyridin-4-yl]-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

A suspension of methyl 4-chloro-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (HP19, 2.0 g, 5.75 mmol, 1.0 equiv), tert-butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3,6-dihydro-2H-pyridine-1-carboxylate (CAS 286961-14-6, 3.6 g, 11.5 mmol, 2.0 equiv), K₂CO₃ (2.4 g, 17.25 mmol, 3.0 equiv) and Pd(dppf)Cl₂ (CAS: 72287-26-4, 939 mg, 1.15 mmol, 0.2 equiv) in anhydrous DMF (15 mL) was degassed with nitrogen at room temperature for 2 minutes. The reaction mixture was refluxed for 20 hours. The mixture was cooled to RT, poured into 150 mL of iced water and diluted with ethyl acetate. The two phases were separated, and the aqueous phase was extracted again with ethyl acetate. The combined organic layers were washed with brine, dried over sodium sulfate, filtered and concentrated. The crude residue was purified by silica gel chromatography (heptane/ethyl acetate: 100/0 to 80/20) to give the titled compound.

Step 2: methyl 4-[1-(tert-butoxycarbonyl)piperidin-4-yl]-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

A suspension of compound from Step 1 (2.44 g, 4.93 mmol, 1.0 equiv) and platinum (IV) oxide (CAS 1314-15-4, 1.2 g) in acetic acid (240 mL) was stirred at RT under a hydrogen atmosphere (balloon) for 20 hours. The reaction mixture was filtered over Celpure® P65. Solids were washed with ethyl acetate, and the filtrate was concentrated in vacuo. The crude residue was purified by silica gel chromatography (heptane/ethyl acetate: 100/0 to 80/20) to give the title compound.

Step 3: methyl 3-cyclobutyl-1-(4-fluorophenyl)-4-(piperidin-4-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Methyl 4-[1-(tert-butoxycarbonyl)piperidin-4-yl]-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (2.75 g, 5.4 mmol, 1 equiv) was dissolved in 4 M HCl in dioxane (40 mL, 162.2 mmol, 30 equiv), and the solution was stirred at RT for 2 hours. The solvent was concentrated under reduced pressure. The residue was dissolved in a minimum of methanol and poured into diethyl ether (500 mL). The precipitate was filtered, washed with diethyl ether and dried at 40° C. under reduced pressure to give the titled compound, E413.

Synthesis of E427 and compound 923: ethyl 4-(4-cyanophenyl)-1-cyclohexyl-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate and 4-(4-cyanophenyl)-1-cyclohexyl-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

A solution of ALP37 (1 g, 4.4 mmol) and 5-amino-1-cyclohexyl-1H-pyrazol-3-ol ([436088-86-7], 796 mg, 4.4 mmol) in N-methylpyrrolidine (7 mL) was heated at 90° C. for 5 hours in a sealed tube. The reaction mixture was cooled to RT. Cesium carbonate (4.3 g, 13.2 mmol) and 2-bromopropane (984 μL, 8.8 mmol) were added, and the tube was sealed. The reaction mixture was heated at 90° C. for 2 hours and then left stirring at RT for 20 hours. The volatiles were removed in vacuo, and the residue was purified by flash chromatography on silica gel eluted with ethyl acetate/n-heptane (0/1 to I/O) to give the titled compound, E427, and the carboxylic acid compound 923.

Synthesis of E428: ethyl 1-(6-bromopyridin-2-yl)-3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

To a solution of E393 (67 mg, 0.16 mmol) in DMA (3 mL) under a nitrogen atmosphere at RT was added sodium hydride (60% in mineral oil, 8 mg, 0.2 mmol), and the mixture was stirred 10 minutes. Then 2-bromo-6-fluoropyridine ([144100-07-2], 56 mg, 0.32 mmol) was added, and the reaction mixture was stirred overnight. The reaction mixture was quenched with a saturated aqueous solution of NH₄Cl and extracted with DCM. The organic phase was washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel eluting with ethyl acetate/DCM/MeOH (100/0/0 to 0/90/10) to afford the titled compound.

Synthesis of E429: methyl 1-(4-fluorophenyl)-4-(4-methoxy[1,4′-bipiperidin]-1′-yl)-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

A pressure vessel was charged with AI25 (145 mg, 240 μmol), Pd(dppf)Cl₂.DCM ([95464-05-4], 4 mg, 4.8 μmol), and triethylamine (66 μL, 500 μmol) in MeOH (5 mL). The system was loaded with CO (6 bars) and heated at 100° C. for 1 hour. The vessel was cooled down to RT, and the mixture was concentrated under reduced pressure. The residue was purified by flash column chromatography eluting with a mixture of ethyl acetate/DCM/MeOH (100/0/0 to 0/90/10) to give the titled compound.

Synthesis of E430: methyl 3-cyclobutyl-4-(1,4-dioxaspiro[4.5]dec-7-en-8-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

In a sealed tube, a suspension of HP02 (1 g, 2.92 mmol), 1,4-dioxa-spiro[4,5]dec-7-en-8-boronic acid, pinacol ester ([680596-79-6], 1.01 g, 3.8 mmol), K₃PO₄ (1.86 g, 8.77 mmol), Pd(OAc)₂ ([3375-31-3], 330 mg, 0.14 mmol), and SPhos ([657408-07-6], 150 mg, 0.365 mmol) in toluene (22 mL) and water (6 mL) was degassed with N₂ at room temperature for 5 minutes. The reaction mixture was stirred at RT for 2 hours. Additional Pd(OAc)₂ ([3375-31-3], 330 mg, 0.14 mmol) and SPhos ([657408-07-6], 150 mg, 0.365 mmol) were added. The stirring at RT was continued for 20 hours. Pd(OAc)2 ([3375-31-3], 165 mg, 0.07 mmol) and SPhos ([657408-07-6], 75 mg, 0.18 mmol) were again added, and the reaction mixture was heated at 100° C. for 1 hour. The reaction mixture was cooled to RT, diluted with ethyl acetate and filtered. The filtrate was washed successively with water and a saturated aqueous solution of NaCl. The organic phase was separated, dried over sodium sulfate, filtered and concentrated under reduced pressure. The crude residue was purified by flash column chromatography on silica gel eluting with ethyl acetate/n-heptane to give the titled compound.

Synthesis of E431: methyl 3-cyclobutyl-4-(1,4-dioxaspiro[4.5]decan-8-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

A suspension of E430 (823 mg, 1.85 mmol) and palladium hydroxide on carbon ([12135-22-7], 280 mg) in THF/MeOH (25 mL, 2/1) was hydrogenated for 20 hours. The reaction mixture was filtered over Celpure® which was washed with DCM. The filtrate was concentrated in vacuo. The residue was purified by silica gel chromatography eluting with ethyl acetate/n-heptane to give the titled compound E431.

Synthesis of E432: methyl 3-cyclobutyl-1-[(3E,5Z)-hepta-1,3,5-trien-4-yl]-4-(4-oxocyclohexyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

The ester, E431 (732 mg, 1.64 mmol), was dissolved in DCM and TFA (2.2 mL, 3 volumes) was added dropwise at RT. The solution was stirred for 48 hours and then diluted with DCM. The mixture was washed with a saturated aqueous solution of NaHCO₃. The organic phase was separated, dried over sodium sulfate, filtered and concentrated in vacuo. The residue was purified by silica gel chromatography eluting with ethyl acetate/n-heptane to give the titled compound E432.

Synthesis of E438: 4-{1-cyclohexyl-6-(ethoxycarbonyl)-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridin-4-yl}benzoic acid

A mixture of aldehyde E425 (27 mg, 62 μmol), sulfamic acid ([226-18-8], 17 mg, 168 μmol), and sodium chlorite ([7758-19-2], 17 mg, 188 μmol) in THF/water (3.3 mL, 10/1) was stirred at RT for 1 hour. The reaction mixture was diluted with DCM (20 mL) and washed with water (20 mL). The organic phase was dried over sodium sulfate, filtered and evaporated under reduced pressure. The titled compound was used as such in the next step.

Synthesis of E444: ethyl 1-cyclohexyl-4-{4-[(8-methyl-2-oxa-5,8-diazaspiro[3.5]nonan-5-yl)methyl]phenyl}-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Iodomethane (3 μL, 48 μmol) was added at RT to a stirred suspension of E443 (22 mg, 40 μmol) and cesium carbonate (33 mg, 100 μmol) in DMF (2 mL). The reaction mixture was stirred for 20 hours. The reaction mixture was partitioned between water and ethyl acetate. The organic phase was dried over sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by flash column chromatography eluting with ethyl acetate/DCM/MeOH (100/0/0 to 0/90/10) to give the titled compound.

Synthesis of E445: ethyl 4-[4-(4-cyano-1-methylpiperidin-4-yl)phenyl]-1-cyclohexyl-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Step 1: ethyl 4-{4-[1-(tert-butoxycarbonyl)-4-cyanopiperidin-4-yl]phenyl}-1-cyclohexyl-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

A solution of ALP38 (305 mg, 0.74 mmol) and AMP95 (575 mg, 0.77 mmol) in N-methylpyrrolidine (4 mL) was heated at 110° C. for 24 hours in an opened vessel. The reaction mixture was cooled to RT, and the mixture was concentrated in vacuo. The residue was partitioned between ethyl acetate and water. The organic phase was separated, dried over sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by flash chromatography on silica gel eluting with ethyl acetate/n-heptane to give the titled compound.

Step 2: ethyl 4-[4-(4-cyanopiperidin-4-yl)phenyl]-1-cyclohexyl-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Trifluoroacetic acid (1 mL) was added to a solution of the tert-butoxycarbonyl protected compound from Step 1 (230 mg, 0.37 mmol) in DCM (10 mL). The solution was stirred at RT for 2 hours. The reaction mixture was diluted with toluene (5 mL) and then concentrated under reduced pressure. The residue was partitioned between ethyl acetate, water, and a phosphate buffer solution (pH 6.2). The organic phase was dried over sodium sulfate, filtered and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel eluting with ethyl acetate/n-heptane to give the titled compound.

Step 3: ethyl 4-[4-(4-cyano-1-methylpiperidin-4-yl)phenyl]-1-cyclohexyl-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Iodomethane (2 μL, 32 μmol) was added at RT to a stirred suspension of the compound from Step 2 (15 mg, 29 μmol) and cesium carbonate (33 mg, 100 μmol) in DMF (2 mL). The reaction mixture was stirred for 2 hours. The reaction mixture was partitioned between water and DCM. The organic phase was dried over sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by flash column chromatography eluting with ethyl acetate/DCM/MeOH (100/0/0 to 0/90/10) to give the titled compound.

Synthesis of E509: methyl 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Step 1: 4-[1-(2,6-dichloropyridin-4-yl)piperidin-4-yl]morpholine

N-Ethyl-N-isopropylpropan-2-amine (22.91 mL, 132 mmol) was added to a suspension of 2,4,6-trichloropyridine (12 g, 65.8 mmol) and 4-(piperidin-4-yl)morpholine (13.44 g, 79 mmol) in acetonitrile (120 mL). The reaction mixture was heated to 60° C. and stirred for 16 hours. Upon cooling to room temperature, the precipitate was collected by filtration. The crude solid was then precipitated from EtOAc to give the titled compound. ¹H NMR (400 MHz, CDCl₃) δ ppm 6.59 (s, 2H), 3.89-3.79 (m, 2H), 3.77-3.69 (m, 4H), 2.96 (ddd, J=13.3, 11.8, 2.8 Hz, 2H), 2.60-2.52 (m, 4H), 2.45 (tt, J=10.8, 3.7 Hz, 1H), 1.95 (ddd, J=12.9, 3.9, 1.9 Hz, 2H), 1.61-1.48 (m, 2H); MS (APCI+) m/z 316.2 (M+H)⁺.

Step 2: cyclobutyl{2,6-dichloro-4-[4-(morpholin-4-yl)piperidin-1-yl]pyridin-3-yl}methanone

n-Butyllithium (19.2 mL, 26.9 mmol) was added in 5 mL portions to a stirred solution of 4-[1-(2,6-dichloropyridin-4-yl)piperidin-4-yl]morpholine (7.95 g, 25.1 mmol) in THF (160 mL) at −78° C. After stirring at this temperature for 1.5 hours, cyclobutanecarbonyl chloride (1.42 g, 11.9 mmol) was added rapidly, and the reaction mixture was stirred for 10 minutes. To obtain higher conversion, sequential additions of n-butyllithium and cyclobutanecarbonyl chloride were performed in the same manner. Addition 1: n-butyllithium (13.0 mL, 18.2 mmol) and cyclobutanecarbonyl chloride (0.97 g, 8.1 mmol); Addition 2: n-butyllithium (9.2 mL, 12.9 mmol) and cyclobutanecarbonyl chloride (0.68 g, 5.6 mmol); Addition 3: n-butyllithium (6.9 mL, 9.7 mmol) and cyclobutanecarbonyl chloride (0.51 g, 4.2 mmol); Addition 4: n-butyllithium (5.7 mL, 8.0 mmol) and cyclobutanecarbonyl chloride (0.41 g, 3.4 mmol). Upon completion of the last addition, the excess n-butyl lithium was quenched with water (200 mL), and the mixture was extracted with ethyl acetate (3×100 mL). The combined organic fractions were washed with brine (100 mL), dried over sodium sulfate, and concentrated in vacuo. The residue was purified by column chromatography (0-5% 95/5 MeOH/30% aqueous NH₃ in DCM) to give the titled compound. ¹H NMR (400 MHz, CDCl₃) δ ppm 6.76 (s, 1H), 3.80-3.65 (m, 5H), 3.50-3.40 (m, 2H), 2.98-2.76 (m, 2H), 2.62-2.50 (m, 4H), 2.50-2.37 (m, 2H), 2.29 (tt, J=11.0, 3.8 Hz, 1H), 2.22-2.08 (m, 2H), 2.08-1.93 (m, 2H), 1.93-1.83 (m, 2H), 1.52 (dddd, J=14.8, 12.8, 7.5, 3.8 Hz, 2H); MS (APCI+) m/z 398.2 (M+H)⁺.

Step 3: 6-chloro-3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine

Hydrazine (35% in water, 3.10 mL, 33.9 mmol) was added to cyclobutyl{2,6-dichloro-4-[4-(morpholin-4-yl)piperidin-1-yl]pyridin-3-yl}methanone (4.5 g, 11.30 mmol) in EtOH (32 mL). The reaction mixture was heated to reflux for 14 hours. Upon cooling to −5° C., the precipitate was isolated by filtration. The filter cake was rinsed with cold EtOH to give the titled compound. ¹H NMR (400 MHz, CDCl₃) δ ppm 10.21 (br s, 1H), 6.45 (s, 1H), 3.94-3.76 (m, 5H), 3.63 (d, J=12.4 Hz, 2H), 2.84 (td, J=12.4, 2.3 Hz, 2H), 2.71-2.59 (m, 4H), 2.58-2.44 (m, 2H), 2.44-2.31 (m, 3H), 2.14-1.97 (m, 4H), 1.85-1.70 (m, 2H); MS (APCI+) m/z 376.2 (M+H)⁺.

Step 4: methyl 3-cyclobutyl-4-(4-morpholinopiperidin-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

Into a 600 mL Parr reactor was charged 6-chloro-3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine (3.4 g, 9.05 mmol), followed by THF (170 mL) and MeOH (170 mL). 1,1′-Bis(diphenylphosphino)ferrocene-palladium (II) dichloride dichloromethane complex (0.739 g, 0.905 mmol), and triethylamine (2.52 mL, 18.09 mmol) were added to give a suspension. The reaction vessel was purged with argon followed by CO, pressurized to 100 psig with CO, and heated to 80° C. After 8 hours, the reaction mixture was cooled to room temperature, diluted with CH₂Cl₂ (800 mL), and filtered. The filtrate was concentrated in vacuo, and the residue was dissolved in CH₂Cl₂ (800 mL). The organic mixture was washed with saturated aqueous NaHCO₃ (300 mL), dried over Na₂SO₄, filtered, and concentrated in vacuo. The crude residue was slurried in EtOAc to give the titled compound. ¹H NMR (400 MHz, CDCl₃) δ ppm 10.98 (br s, 1H), 7.37 (s, 1H), 4.08 (s, 3H), 3.96 (p, J=8.4 Hz, 1H), 3.83-3.76 (m, 4H), 3.70 (d, J=12.3 Hz, 2H), 2.92 (t, J=11.8 Hz, 2H), 2.66 (t, J=4.7 Hz, 4H), 2.55 (dq, J=11.3, 9.0 Hz, 2H), 2.44-2.31 (m, 3H), 2.15-2.00 (m, 4H), 1.88-1.74 (m, 2H); MS (APCI+) m/z 400.3 (M+H)⁺.

TABLE XIII List of esters Int. Structure Name SM method MW Mes E001

ethyl 1-(3- bromophenyl)-3- isopropyl-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate AI17 I9 548- 550 549- 551 E002

ethyl 1-[3-(azetidin- 1-yl)phenyl]-3- isopropyl-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E001, 935670- 07-8 I8 525 526 E003

ethyl 1-cyclohexyl- 3-isopropyl-4-(2- morpholinopyrimidin- 5-yl)pyrazolo[3,4- b]pyridine-6- carboxylate ALP22, AMP23 I1 478 479 E004

ethyl 3-methyl-1- phenyl-4-(1- piperidyl)pyrazolo[3, 4-b]pyridine-6- carboxylate HP13, 98-77-1 I3 364 365 E005

ethyl 3-isopropyl-4- (4-morpholinophenyl)- 1-(3-pyrrolidin-1- ylphenyl)pyrazolo[3, 4-b]pyridine-6- carboxylate E001 I8 539 540 E006

ethyl 4-[4- (dimethylamino) phenyl]-3-methyl-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate ALP25, 1131-18- 6 I1 400 401 E007

ethyl 3-isopropyl-4- (6-morpholino-3- pyridyl)-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP26, AMP04 I1 471 472 E008

ethyl 3-isopropyl-1- [3-(3- methoxyazetidin-1- yl)phenyl]-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E001, 110925- 17-2 I8 555 556 E009

ethyl 3-methyl-4-(6- morpholino-3- pyridyl)-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP26, 1131-18- 6 I1 443 444 E010

ethyl 4-(4- bromophenyl)-3- methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate AI16 I9 435- 437 436- 438 E011

ethyl 4-[4-[3- (dimethylamino) azetidin-1-yl]phenyl]- 3-methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010, 138022- 85-2 I10 455 456 E012

ethyl 1-[3-(3,3- dimethylazetidin-1- yl)phenyl]-3- isopropyl-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E001, 19816- 92-3 I8 553 554 E013

ethyl 1-[3-(3- fluoropyrrolidin-1- yl)phenyl]-3- isopropyl-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E001, 116574- 74-4 I8 553 558 E014

ethyl 1-cyclohexyl- 3-isopropyl-4-[6- [methyl (tetrahydropyran- 4-yl)amino]-3- pyridyl]pyrazolo[3,4- b]pyridine-6- carboxylate ALP10, AMP23 I1 505 506 E015

ethyl 1-[3- (dimethylamino) phenyl]-3-isopropyl- 4-(6-morpholino-3- pyridyl)pyrazolo[3,4- b]pyridine-6- carboxylate ALP26, AMP06 I1 514 515 E016

ethyl 1-[3- (dimethylamino) phenyl]-3-isopropyl- 4-(2-morpholino- pyrimidin- 5-yl)pyrazolo[3,4- b]pyridine-6- carboxylate ALP22, AMP06 I1 515 516 E017

ethyl 3-cyclobutyl-4- [6-[2- methoxyethyl(methyl) amino]-3-pyridyl]- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP08, AMP26 I1 485 486 E018

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3- cyclobutyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP29 I1 506 507 E019

ethyl 3-cyclobutyl-4- [6-[methyl (tetrahydropyran- 4-yl)amino]-3- pyridyl]-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP10, AMP29 I1 511 512 E020

ethyl 3-cyclobutyl-4- [4-[2- methoxyethyl(methyl) amino]phenyl]-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate ALP11, AMP29 I1 484 485 E021

ethyl 4-(4- acetamidophenyl)-1- cyclohexyl-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP24, AMP23 I1 448 449 E022

ethyl 4-[4-(4-cyano- 1-piperidyl)phenyl]- 1-cyclohexyl-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP12, AMP23 I1 499 500 E023

ethyl 4-[4-(4-cyano- 1-piperidyl)phenyl]- 1-[3-(dimethylamino) phenyl]-3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP12, AMP06 I1 536 537 E024

ethyl 1-[3- (dimethylamino) phenyl]-3- isopropyl-4-[4-[2- methoxyethyl(methyl) amino]phenyl] pyrazolo [3,4-b]pyridine-6- carboxylate ALP11, AMP06 I1 515 516 E025

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-1-[3- (dimethylamino) phenyl]-3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP06 I1 537 538 E026

ethyl 1-[3- (dimethylamino) phenyl]-3-isopropyl- 4-[6-[2- methoxyethyl(methyl) amino]-3- pyridyl]pyrazolo[3,4- b]pyridine-6- carboxylate ALP08, AMP06 I1 516 517 E027

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3-isopropyl- 1-(3-morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP10 I1 579 580 E028

ethyl 3-isopropyl-4- [6-[2- methoxyethyl(methyl) amino]-3-pyridyl]- 1-(3-morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate ALP08, AMP10 I1 558 559 E029

ethyl 3-isopropyl-4- [6-[methyl (tetrahydropyran- 4-yl)amino]-3- pyridyl]-1-(3- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate ALP10, AMP10 I1 584 585 E030

ethyl 3-isopropyl-4- [4-[2- methoxyethyl(methyl) amino]phenyl]-1-(3- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate ALP11, AMP10 I1 557 558 E031

ethyl 1-[3- (dimethylamino) phenyl]-3-isopropyl- 4-[6-[methyl (tetrahydropyran- 4-yl)amino]-3- pyridyl]pyrazolo[3,4- b]pyridine-6- carboxylate ALP10, AMP06 I1 542 543 E032

ethyl 1-[3- (dimethylamino) phenyl]-3-isopropyl- 4-[2-[methyl (tetrahydropyran-4- yl)amino]pyrimidin- 5-yl]pyrazolo[3,4- b]pyridine-6- carboxylate ALP13, AMP06 I1 543 544 E033

ethyl 1-cyclohexyl- 3-cyclopropyl-4-[6- (dimethylamino)-3- pyridyl]pyrazolo[3,4- b]pyridine-6- carboxylate ALP20, AMP39 I1 433 434 E034

ethyl 4-[2-(4-cyano-1- piperidyl)pyrimidin- 5-yl]-1-[3- (dimethylamino) phenyl]-3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP14, AMP06 I1 538 539 E035

ethyl 1-[3- (dimethylamino) phenyl]-3-isopropyl- 4-[4-[methyl (tetrahydropyran-4- yl)amino]phenyl] pyrazolo [3,4-b]pyridine- 6-carboxylate ALP15, AMP06 I1 541 542 E036

ethyl 3-isopropyl-4- [4-[methyl (tetrahydropyran-4- yl)amino]phenyl]-1- (3-morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate ALP15, AMP10 I1 583 584 E037

ethyl 4-[2-(4-cyano-1- piperidyl)pyrimidin- 5-yl]-3-isopropyl-1- (3-morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate ALP14, AMP10 I1 580 581 E038

ethyl 4-[4-[3- (dimethylamino) pyrrolidin-1-yl] phenyl]- 3-methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010, 69478- 75-7 I10 469 470 E039

ethyl 3-isopropyl-1- (m-tolyl)-4-(1- piperidyl)pyrazolo[3, 4-b]pyridine-6- carboxylate HP01, 98-77-1 I3 406 407 E040

ethyl 4-[4-(4-cyano- 1-piperidyl)phenyl]- 3-cyclobutyl-1- cyclohexyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP12, AMP35 I1 511 512 E041

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3- cyclobutyl-1- cyclohexyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP35 I1 512 513 E042

ethyl 4-(4- acetamidophenyl)-1- (3,5-difluorophenyl)- 3-(1-methoxycarbonyl- azetidin-3- yl)pyrazolo[3,4- b]pyridine-6- carboxylate E043 I11B 549 550 E043

ethyl 4-(4- acetamidophenyl)-3- (azetidin-3-yl)-1- (3,5-difluorophenyl) pyrazolo [3,4-b]pyridine-6- carboxylate E044 I21A 491 492 E044

ethyl 4-(4- acetamidophenyl)-3- (1-tert- butoxycarbonyl- azetidin-3-yl)-1-(3,5- difluorophenyl) pyrazolo [3,4-b]pyridine-6- carboxylate ALP24, AMP40 I1 591 592 E045

ethyl 3-isopropyl-4- [4-[2- methoxyethyl(methyl) amino]phenyl]-1-(3- pyrrolidin-1- ylphenyl)pyrazolo[3, 4-b]pyridine-6- carboxylate ALP11, AMP11 I1 541 542 E046

ethyl 3-isopropyl-4- [4-[methyl (tetrahydropyran-4- yl)amino]phenyl]-1- (3-pyrrolidin-1- ylphenyl)pyrazolo[3, 4-b]pyridine-6- carboxylate ALP15, AMP11 I1 567 568 E047

ethyl 3-cyclobutyl-4- [4-[methyl (tetrahydropyran-4- yl)amino]phenyl]-1- (3-pyrrolidin-1- ylphenyl)pyrazolo[3, 4-b]pyridine-6- carboxylate ALP15, AMP31 I1 580 581 E048

ethyl 3-isopropyl-4- (4-methoxy-1- piperidyl)-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01, 4045-24- 3 I3 436 437 E049

ethyl 4-[2-(4-cyano- 1-piperidyl)pyrimidin- 5-yl]-1-cyclohexyl- 3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP14, AMP23 I1 501 502 E050

ethyl 1-cyclohexyl- 3-isopropyl-4-[2-[2- methoxyethyl(methyl) amino]pyrimidin-5- yl]pyrazolo[3,4- b]pyridine-6- carboxylate ALP16, AMP23 I1 480 481 E051

ethyl 1-cyclohexyl- 3-isopropyl-4-[2- [methyl (tetrahydropyran-4- yl)amino]pyrimidin- 5-yl]pyrazolo[3,4- b]pyridine-6- carboxylate ALP13, AMP23 I1 506 507 E052

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3-isopropyl- 1-[3-(trifluoromethyl) phenyl]pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP08 I1 562 563 E053

ethyl 1-[6- (dimethylamino)-2- pyridyl]-3-isopropyl- 4-(4-morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate ALP18, AMP18 I1 514 515 E054

ethyl 3-isopropyl-4- (4-morpholinophenyl)- 1-[3-(trifluoromethoxy) phenyl]pyrazolo[3,4- b]pyridine-6- carboxylate E055, 179113- 90-7 I4 554 555 E055

ethyl 3-isopropyl-4- (4-morpholinophenyl)- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E056 I15 394 395 E056

ethyl 1-[(2,4- dimethoxyphenyl) methyl]-3-isopropyl- 4-(4-morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate ALP18, AMP28 I1 544 545 E057

ethyl 1-(3,4- difluorophenyl)-3- isopropyl-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E055 I4 506 507 E058

ethyl 3-isopropyl-4- (4-morpholinophenyl)- 1-(6-morpholino-2- pyridyl)pyrazolo[3,4- b]pyridine-6- carboxylate ALP18, AMP19 I1 556 557 E059

ethyl 4-(2,6-difluoro- 4-methoxy-phenyl)- 1-(3-fluoro-5- methoxy-phenyl)-3- methyl-pyrazolo[3,4- b]pyridine-6- carboxylate ALP17, AMP03 I1 471 472 E060

ethyl 4-[4-(4-cyano- 1-piperidyl)phenyl]- 1-(3,5- difluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP12, AMP09 I1 529 530 E061

ethyl 4-[4-(4-cyano- 1-piperidyl)phenyl]- 1-(3-fluorophenyl)- 3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP12, AMP12 I1 511 512 E062

ethyl 3-isopropyl-4- [4-[2- methoxyethyl(methyl) amino]phenyl]-1-[3- (trifluoromethyl) phenyl]pyrazolo[3,4- b]pyridine-6- carboxylate ALP11, AMP08 I1 540 541 E063

ethyl 3-isopropyl-4- [6-[methyl (tetrahydropyran- 4-yl)amino]-3- pyridyl]-1-[3- (trifluoromethyl) phenyl]pyrazolo[3,4- b]pyridine-6- carboxylate ALP10, AMP08 I1 567 568 E064

ethyl 1-(4- fluorophenyl)-3- isopropyl-4-[2- [methyl (tetrahydropyran-4- yl)amino]pyrimidin- 5-yl]pyrazolo[3,4- b]pyridine-6- carboxylate ALP13, AMP13 I1 518 519 E065

ethyl 4-[4-(4-cyano- 1-piperidyl)phenyl]- 3-isopropyl-1-[3- (trifluoromethyl) phenyl] pyrazolo[3,4- b]pyridine-6- carboxylate ALP12, AMP08 I1 561 562 E066

ethyl 3-isopropyl-4- (4-morpholinophenyl)- 1-(2-morpholino-4- pyridyl)pyrazolo[3,4- b]pyridine-6- carboxylate ALP18, AMP21 I1 556 557 E067

ethyl 3-(1- methylcyclobutyl)-4- (4-morpholinophenyl)- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP18, AMP41 I1 496 497 E068

ethyl 4-[2-(4-cyano- 1-piperidyl)pyrimidin- 5-yl]-1-(2,4- difluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP14, AMP14 I1 531 532 E069

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-1-(2,4- difluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP14 I1 530 531 E070

ethyl 4-[4-(4-cyano- 1-piperidyl)phenyl]- 1-(2,4- difluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP12, AMP14 I1 529 530 E071

methyl 3-cyclobutyl- 4-(4-methoxy-1- piperidyl)-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 420 421 E072

ethyl 1-[3- (dimethylamino) phenyl]-3-isopropyl-4- [4-(methoxymethyl)- 1-piperidyl]pyrazolo[3, 4-b]pyridine-6- carboxylate HP03 I3 479 480 E073

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3-isopropyl- 1-tetrahydropyran-3- yl-pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP25 I1 502 503 E074

ethyl 4-[4-(3- benzyloxypyrrolidin- 1-yl)phenyl]-3- methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate AI12 I9 532 533 E075

ethyl 4-(2,2-difluoro- 5-azaspiro[2.4]heptan- 5-yl)-3-isopropyl-1- (m-tolyl) pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 454 455 E076

ethyl 1-cyclohexyl- 3-isopropyl-4-(4- methoxy-1- piperidyl)pyrazolo[3, 4-b]pyridine-6- carboxylate HP04 I3 428 429 E077

methyl 3-cyclobutyl- 4-(4-isopropoxy-1- piperidyl)-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 448 449 E078

methyl 3-cyclobutyl- 1-phenyl-4-(4- propoxy-1- piperidyl)pyrazolo[3, 4-b]pyridine-6- carboxylate HP02 I3 448 449 E079

methyl 3-cyclobutyl- 4-[3- (methoxymethyl)-1- piperidyl]-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 434 435 E080

methyl 3-cyclobutyl- 4-[4-(2-oxo-2- pyrrolidin-1-yl- ethoxy)-1-piperidyl]- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 517 518 E081

ethyl 1-[3- (dimethylamino) phenyl]-3-isopropyl- 4-(4-methoxy-1- piperidyl)pyrazolo[3, 4-b]pyridine-6- carboxylate HP03 I3 465 466 E082

ethyl 3-isopropyl-4- [4-(methoxymethyl)- 1-piperidyl]-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 450 451 E083

ethyl 1-[3- (dimethylamino) phenyl]-3-isopropyl- 4-(1- piperidyl)pyrazolo[3, 4-b]pyridine-6- carboxylate HP03 I3 435 436 E084

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3-isopropyl- 1-(2-pyrrolidin-1-yl- 4- pyridyl)pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP22 I1 564 565 E085

methyl 3-cyclobutyl- 4-(1-oxa-7- azaspiro[3.5]nonan- 7-yl)-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 432 433 E086

ethyl 4-(4-cyano-1- piperidyl)-1-[3- (dimethylamino) phenyl]-3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP03 I3 460 461 E087

ethyl 3-isopropyl-4- [4-(2-methoxyethyl)- 1-piperidyl]-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 464 465 E088

ethyl 3-isopropyl-4- (3-methoxy-1- piperidyl)-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 436 437 E089

ethyl 3-isopropyl-4- (4-methylsulfonyl-1- piperidyl)-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 484 485 E090

isopropyl 3- isopropoxy-4-(4- morpholinophenyl)- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate AI15 I17 500 501 E091

methyl 1-(4- fluorophenyl)-3- isopropyl-4-(4- methoxy-1- piperidyl)pyrazolo[3, 4-b]pyridine-6- carboxylate HP05 I3 426 427 E092

methyl 1-(4- fluorophenyl)-3- isopropyl-4-[4- (methoxymethyl)-1- piperidyl]pyrazolo[3, 4-b]pyridine-6- carboxylate HP05 I3 440 441 E093

ethyl 4-[4-(4-cyano- 1-piperidyl)phenyl]- 3-isopropyl-1-(2- pyrrolidin-1-yl-4- pyridyl)pyrazolo[3,4- b]pyridine-6- carboxylate ALP12, AMP22 I1 563 564 E094

ethyl 3-isopropyl-4-[2- methoxyethyl(methyl) amino]-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 410 411 E095

ethyl 3-isopropyl-1- (m-tolyl)-4-(8-oxa-2- azaspiro[4.5]decan- 2-yl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 462 463 E096

methyl 4-(4-butoxy- 1-piperidyl)-1-(4- fluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 468 467 E097

methyl 1-(4- fluorophenyl)-3- isopropyl-4-(4- methoxy-4-methyl-1- piperidyl)pyrazolo[3, 4-b]pyridine-6- carboxylate HP05 I3 440 441 E098

methyl 1-(4- fluorophenyl)-4-(4- isobutoxy-1- piperidyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 468 469 E099

methyl 1-(4- fluorophenyl)-3- isopropyl-4-(1-oxa-7- azaspiro[3.5]nonan- 7-yl)pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 438 439 E100

methyl 4-[3- (difluoromethyl)-1- piperidyl]-1-(4- fluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 446 447 E101

methyl 1-(4- fluorophenyl)-3- isopropyl-4-(6-oxa-2- azaspiro[3.5]nonan- 2-yl)pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 438 439 E102

methyl 1-(4- fluorophenyl)-3- isopropyl-4-(1-oxa-8- azaspiro[4.5]decan- 8-yl)pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 452 453 E103

methyl 3-cyclobutyl- 1-phenyl-4-(1- piperidyl)pyrazolo[3, 4-b]pyridine-6- carboxylate HP02 I3 390 391 E104

methyl 3-cyclobutyl- 4-[4-(2- methoxyethyl)-1- piperidyl]-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 448 449 E105

methyl 4-(2- azaspiro[3.4]octan-2- yl)-3-cyclobutyl-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 416 417 E106

methyl 3-cyclobutyl- 4-[4- (methoxymethyl)-1- piperidyl]-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 434 435 E107

methyl 4-(3- azabicyclo[3.1.0] hexan-3-yl)-3- cyclobutyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 388 389 E108

ethyl 1-(2-bromo-4- pyridyl)-3-isopropyl- 4-(4-methoxy-1- piperidyl)pyrazolo[3, 4-b]pyridine-6- carboxylate E109 I4 501-503 502-504 E109

ethyl 3-isopropyl-4- (4-methoxy-1- piperidyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP08 I3 346 347 E110

ethyl 3-isopropyl-4- (4-methoxy-1- piperidyl)-1-(2- pyrrolidin-1-yl-4- pyridyl)pyrazolo[3,4- b]pyridine-6- carboxylate E111 I12 492 493 E111

ethyl 1-(2-fluoro-4- pyridyl)-3-isopropyl- 4-(4-methoxy-1- piperidyl)pyrazolo[3, 4-b]pyridine-6- carboxylate E109 I4 441 442 E112

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3- cyclobutyl-1-(2- pyrrolidin-1-yl-4- pyridyl)pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP34 I1 576 577 E113

methyl 3-cyclobutyl- 4-(4-methylsulfonyl- 1-piperidyl)-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 468 469 E114

methyl 4-(4-cyanol-1- piperidyl)-3- cyclobutyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 415 416 E115

methyl 4-(2- azaspiro[3.5]nonan- 2-yl)-3-cyclobutyl-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 430 431 E116

methyl 3-cyclobutyl- 4-[3-(methoxymethyl) azetidin- 1-yl]-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 406 407 E117

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3-(3- methoxycyclobutyl)- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP42 I1 536 537 E118

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3-(3,3- difluorocyclobutyl)- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP43 I1 542 543 E119

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3-(3,3- dimethylcyclobutyl)- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP44 I1 534 535 E120

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3-(3- fluorocyclobutyl)-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP45 I1 524 525 E121

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3- cyclobutyl-1-(2- morpholino-4- pyridyl)pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP33 I1 592 593 E122

methyl 3-cyclobutyl- 4-(2,2-difluoro-5- azaspiro[2.4]heptan- 5-yl)-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 438 439 E123

methyl 3-cyclobutyl- 4-(5-oxa-2- azaspiro[3.5]nonan- 2-yl)-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 432 433 E124

methyl 3-cyclobutyl- 4-(7-oxa-2- azaspiro[3.5]nonan- 2-yl)-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 432 433 E125

methyl 4-(5- azaspiro[2.5]octan-5- yl)-3-cyclobutyl-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 416 417 E126

methyl 3-cyclobutyl- 4-[2- methoxyethyl(methyl) amino]-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 394 395 E127

methyl 4-[4- (benzyloxymethyl)- 1-piperidyl]-3- cyclobutyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 510 511 E128

methyl 4-(2- azaspiro[3.3]heptan- 2-yl)-3-cyclobutyl-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 402 403 E129

methyl 3-cyclobutyl- 4-(1- methoxycarbonyl- 3,3a,4,6,7,7a- hexahydro-2H- pyrrolo[3,2- c]pyridin-5-yl)-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate E130 I11B 489 490 E130

methyl 4- (1,2,3,3a,4,6,7,7a- octahydropyrrolo[3,2- c]pyridin-5-yl)-3- cyclobutyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E131 I21B 431 432 E131

methyl 4-(1-tert- butoxycarbonyl- 3,3a,4,6,7,7a- hexahydro-2H- pyrrolo[3,2- c]pyridin-5-yl)-3- cyclobutyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 531 532 E132

methyl 4-(1-acetyl- 3,3a,4,6,7,7a- hexahydro-2H- pyrrolo[3,2- c]pyridin-5-yl)-3- cyclobutyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E130 I11B 473 474 E133

ethyl 1-(6-bromo-2- pyridyl)-3-isopropyl- 4-(4-methoxy-1- piperidyl)pyrazolo[3, 4-b]pyridine-6- carboxylate E109 I5 501- 503 502- 504 E134

methyl 1-cyclohexyl- 4-[4- (hydroxymethyl)-1- piperidyl]-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP12 I3 414 415 E135

methyl 3-cyclobutyl- 4-[4-[(1S)-2- (dimethylamino)-1- fluoro-ethyl]-1- piperidyl]-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02, AMI03 I3 479 480 E136

methyl 1-(4- fluorophenyl)-4-[4- (1-hydroxy-1- methyl-ethyl)-1- piperidyl]-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 454 455 E137

ethyl 1-(3- fluorophenyl)-3- isopropyl-4-[6- [methyl (tetrahydropyran- 4-yl)amino]-3- pyridyl]pyrazolo[3,4- b]pyridine-6- carboxylate ALP10, AMP12 I1 517 518 E138

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3-isopropyl- 1-(2-morpholino-4- pyridyl)pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP21 I1 580 581 E139

methyl 3-cyclobutyl- 4-[4-(cyclopentoxy)- 1-piperidyl]-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 474 475 E140

methyl 3-cyclobutyl- 4-[4-(cyclohexoxy)- l-piperidyl]-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 488 489 E141

methyl 3-cyclobutyl- 4-[4- (cyclopropylmethoxy)- 1-piperidyl]-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 460 461 E142

ethyl 4-(4-cyano-1- piperidyl)-1-(4- fluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP09 I3 435 436 E143

methyl 3-cyclobutyl- 4-[4-(1- hydroxyethyl)-1- piperidyl]-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 434 435 E144

methyl 3-cyclobutyl- 1-phenyl-4-[4-(2,2,2- trifluoro-1-hydroxy- 1-methyl-ethyl)-1- piperidyl]pyrazolo[3, 4-b]pyridine-6- carboxylate HP02 I3 502 503 E145

ethyl 4-[6-[bis(2- methoxyethyl)amino]- 3-pyridyl]-3- cyclobutyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate ALP23, AMP29 I1 529 530 E146

methyl 3-cyclobutyl- 4-[4-hydroxy-4- (methoxymethyl)-1- piperidyl]-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02, AMI01 I3 450 451 E147

ethyl 1-(2-fluoro-4- pyridyl)-3-isopropyl- 4-[4- (methoxymethyl)-1- piperidyl]pyrazolo[3, 4-b]pyridine-6- carboxylate E148 I4 455 456 E148

ethyl 3-isopropyl-4- [4-(methoxymethyl)- 1-piperidyl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP08 I3 360 361 E149

ethyl 4-[6-[bis(2- methoxyethyl)amino]- 3-pyridyl]-3- isopropyl-1-(2- morpholino-4- pyridyl)pyrazolo[3,4- b]pyridine-6- carboxylate ALP23, AMP21 I1 603 604 E150

methyl 3-cyclobutyl- 4-[4-[(1,1-dioxo-1,4- thiazinan-4- yl)methyl]-4- hydroxy-1- piperidyl]-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02, AMI02 I3 553 554 E151

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3-(3- methylcyclobutyl)-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, AMP46 I1 520 521 E152

ethyl 3-[(1-tert- butoxycarbonyl-4- piperidyl)oxy]-4-[6- (4-cyano-1- piperidyl)-3- pyridyl]-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E153 I3 651 E153

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3-oxo-1- phenyl-2H- pyrazolo[3,4- b]pyridine-6- carboxylate ALP09, 70373- 98-7 I1 468 469 E154

ethyl 1- (cyclobutylmethyl)- 3-isopropyl-4-[4- (methoxymethyl)-1- piperidyl]pyrazolo[3, 4-b]pyridine-6- carboxylate E148 I6 428 429 E155

ethyl 1-isobutyl-3- isopropyl-4-[4- (methoxymethyl)-1- piperidyl]pyrazolo[3, 4-b]pyridine-6- carboxylate E148 I6 416 417 E156

methyl 1-(4- fluorophenyl)-3- isopropyl-4-[4- (2,2,2- trifluoroethyl)piperazin- 1-yl]pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 479 480 E157

ethyl 3-isopropyl-4- [4-(methoxymethyl)- 1-piperidyl]-1-(1- methyl-6-oxo- pyridazin-3- yl)pyrazolo[3,4- b]pyridine-6- carboxylate E148 I7 468 469 E158

methyl 3-cyclobutyl- 4-(4- isopropylpiperazin- 1-yl)-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 433 434 E159

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-1-phenyl-3- tetrahydrofuran-3- yloxy-pyrazolo[3,4- b]pyridine-6- carboxylate E153 I13 538 539 E160

ethyl 3-isopropyl-4- [4-(methoxymethyl)- 1-piperidyl]-1-(2- morpholinopyrimidin- 4-yl)pyrazolo[3,4- b]pyridine-6- carboxylate E161 I12 523 524 E161

ethyl 1-(2- chloropyrimidin-4- yl)-3-isopropyl-4-[4- (methoxymethyl)-1- piperidyl]pyrazolo[3, 4-b]pyridine-6- carboxylate E148 I5 472- 474 473- 475 E162

methyl 4-(4- cyclobutylpiperazin- 1-yl)-1-(4- fluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 451 452 E163

methyl 3-cyclobutyl- 4-[4-(1-hydroxy-1- methyl-ethyl)-1- piperidyl]-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 448 449 E164

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3-(oxetan-3- yloxy)-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E153 I13 524 525 E165

methyl 1-(4- fluorophenyl)-3- isopropyl-4-[2- methoxyethyl(methyl) amino]pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 400 401 E166

methyl 1-(4- fluorophenyl)-4-[4- (1-hydroxy-1- methyl-ethyl)-1- piperidyl]-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 454 455 E167

ethyl 3-cyclobutyl-1- (4-fluorophenyl)-4- [4-(methoxymethyl)- 1-piperidyl]pyrazolo[3, 4-b]pyridine-6- carboxylate E168 I4 466 467 E168

ethyl 3-cyclobutyl-4- [4-(methoxymethyl)- 1-piperidyl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E169 I15 372 373 E169

ethyl 3-cyclobutyl-1- [(2,4- dimethoxyphenyl) methyl]-4-[4- (methoxymethyl)-1- piperidyl]pyrazolo[3, 4-b]pyridine-6- carboxylate HP14 I3 522 523 E170

methyl 3-cyclobutyl- 4-[4-(1-hydroxy-1- methyl-ethyl)-1- piperidyl]-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 448 449 E171

ethyl 3-cyclobutyl-1- (4-fluorophenyl)-4- (tetrahydropyran-4- ylmethoxy)pyrazolo [3,4-b]pyridine-6- carboxylate E172 I16 453 454 E172

ethyl 3-cyclobutyl-4- (tetrahydropyran-4- ylmethoxy)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E173 I15 359 360 E173

ethyl 3-cyclobutyl-1- [(2,4- dimethoxyphenyl) methyl]-4- (tetrahydropyran-4- ylmethoxy)pyrazolo [3,4-b]pyridine-6- carboxylate HP15 I14 509 510 E174

methyl 4-[4- (dimethylamino)-1- piperidyl]-1-(4- fluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 439 440 E175

methyl 1-(4- fluorophenyl)-3- isopropyl-4-[4-(1- methyl-4-piperidyl)-1- piperidyl]pyrazolo[3, 4-b]pyridine-6- carboxylate HP05 I3 493 494 E176

methyl 4-[(l-acetyl-4- piperidyl)methoxy]- 1-(4-fluorophenyl)- 3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate E177 I11B 468 469 E177

methyl 1-(4- fluorophenyl)-3- isopropyl-4-(4- piperidylmethoxy) pyrazolo[3,4- b]pyridine-6- carboxylate AI22 I9 426 427 E178

methyl 1-(4- fluorophenyl)-3- isopropyl-4-[(1- methoxycarbonyl-4- piperidyl)methoxy] pyrazolo[3,4- b]pyridine-6- carboxylate E177 I11B 484 485 E179

methyl 4-[4- (cyanomethyl)-4- hydroxy-1- piperidyl]-3- cyclobutyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02, AMI09 I3 445 446 E180

methyl 3-cyclobutyl- 1-phenyl-4-[4-(2,2,2- trifluoroethyl)piperazin- 1-yl]pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 473 474 E181

ethyl 1-(2-fluoro-4- pyridyl)-3-isopropyl- 4-(tetrahydropyran-4- ylmethoxy)pyrazolo [3,4-b]pyridine-6- carboxylate E182 I4 442 443 E182

ethyl 3-isopropyl-4- (tetrahydropyran-4- ylmethoxy)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E183 I15 347 348 E183

ethyl l-[(2,4- dimethoxyphenyl) methyl]-3-isopropyl-4- (tetrahydropyran-4- ylmethoxy)pyrazolo [3,4-b]pyridine-6- carboxylate HP06 I14 497 498 E184

methyl 4-(4- ethoxycarbonyl- piperazin- 1-yl)-1-(4- fluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 469 470 E185

methyl 1-(4- fluorophenyl)-3- isopropyl-4-(3- methyl-2-oxo-1-oxa- 3,8- diazaspiro[4.5]decan- 8-yl)pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 481 482 E186

methyl 1-(4- fluorophenyl)-3- isopropyl-4-[3- (trifluoromethyl) piperazin-1- yl]pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 465 466 E187

methyl 1-(4- fluorophenyl)-3- isopropyl-4-[4-(2- methoxyethyl) piperazin-1- yl]pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 455 456 E188

methyl 4-(2,4-dioxo- 1,3,8- triazaspiro[4.5]decan- 8-yl)-1-(4- fluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 480 481 E189

methyl 4-[4- (ethoxymethyl)-4- fluoro-1-piperidyl]- 1-(4-fluorophenyl)- 3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05, AMI04 I3 472 473 E190

methyl 4-[4-fluoro- 4-(2- methoxyethoxymethyl)- 1-piperidyl]-1-(4- fluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05, AMI05 I3 502 503 E191

methyl 4-[(3R,4R)-3- fluoro-4-hydroxy-1- piperidyl]-1-(4- fluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05, AMI06 I3 430 431 E192

methyl 4-[4-fluoro- 4-(methoxymethyl)- 1-piperidyl]-1-(4- fluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05, AMI07 I3 458 459 E193

methyl 4-[3-fluoro- 3-(2- methoxyethoxymethyl)- 1-piperidyl]-1-(4- fluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05, AMI08 I3 502 503 E194

methyl 1-(4- fluorophenyl)-3- isopropyl-4-[4-(1- piperidyl)-1- piperidyl]pyrazolo[3, 4-b]pyridine-6- carboxylate HP05 I3 479 480 E195

ethyl 1-(2,6- dimethyl-4-pyridyl)- 3-isopropyl-4-[4- (methoxymethyl)-1- piperidyl]pyrazolo[3, 4-b]pyridine-6- carboxylate E148 I4 465 466 E196

methyl 3-cyclobutyl- 4-(1,1-dioxo-1,4- thiazinan-4-yl)-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 440 441 E197

methyl 4-(1-tert- butoxycarbonyl-4- piperidyl)-1-(4- fluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate E198 Specific example 496 497 E198

methyl 4-(1-tert- butoxycarbonyl-3,6- dihydro-2H-pyridin- 4-yl)-1-(4- fluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I2, Specific example 494 495 E199

methyl 4-(4- azidophenyl)-1-[3- (dimethylamino) phenyl]-3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate E200 Specific example 455 456 E200

methyl 4-(4- bromophenyl)-1-[3- (dimethylamino) phenyl]-3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate 608128- 34-3, AMP06 I1 492- 494 493- 495 E201

ethyl 3-methyl-4-[4-(4- methylsulfonyl- piperazin- 1-yl)phenyl]-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate E324 I11A 519 520 E202

ethyl 4-[4-(4-tert- butylpiperazin-1- yl)phenyl]-3-methyl- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 497 498 E203

ethyl 4-[4-(4- methoxycarbonyl- piperazin-1-yl)phenyl]- 3-methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E324 I11B 499 500 E204

ethyl 1-(1-acetyl-4- piperidyl)-3- isopropyl-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E325 I11B 519 520 E205

ethyl 4-[4-(3,3- dimethylazetidin-1- yl)phenyl]-3-methyl- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 440 441 E206

ethyl 3-methyl-1- phenyl-4-[4-[4- (3,3,3- trifluoropropyl) piperazin-1- yl]phenyl]pyrazolo[3, 4-b]pyridine-6- carboxylate E324 I18 537 538 E208

ethyl 1-[1- (cyanomethyl)-4- piperidyl]-3- isopropyl-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E325 I18 516 517 E209

ethyl 4-[4-(3,3- difluoroazetidin-1- yl)phenyl]-3-methyl- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 448 449 E210

ethyl 4-[4-[4- (cyanomethyl) piperazin- 1-yl]phenyl]-3- methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E324 I18 480 481 E211

ethyl 4-[4-[4-(2- hydroxyethyl) piperazin- 1-yl]phenyl]-3- methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E324 I18 485 486 E212

ethyl 4-[4-(4,4- difluoro-1- piperidyl)phenyl]-3- methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 476 477 E213

ethyl 4-[4-(4-cyano- 1-piperidyl)phenyl]- 3-methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 465 466 E214

ethyl 3-methyl-4-[4- [methyl (tetrahydropyran-4- yl)amino]phenyl]-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 470 471 E215

ethyl 4-[4-(3,3- difluoropyrrolidin-1- yl)phenyl]-3-methyl- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 462 463 E216

ethyl 3-methyl-4-[4- (oxetan-3- ylamino)phenyl]-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 428 429 E217

ethyl 4-[4-(2,6- dimethylmorpholin- 4-yl)phenyl]-3- methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 470 471 E218

methyl 4-[4- [cyclobutyl(methyl) amino]phenyl]-3- methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E337 I18 426 427 E219

ethyl 4-[4-[(3R,4R)- 3,4- dihydroxypyrrolidin- 1-yl]phenyl]-3- methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 458 459 E220

ethyl 3-isopropyl-4-(4- morpholinophenyl)- 1-[1-(2,2,2- trifluoroethyl)-4- piperidyl]pyrazolo[3, 4-b]pyridine-6- carboxylate E325 I18 559 560 E221

ethyl 4-[4-(2,2- dimethylmorpholin- 4-yl)phenyl]-3- methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 470 471 E222

ethyl 3-isopropyl-1-(3- morpholinophenyl)- 4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E001 I8 555 556 E223

ethyl 4-[4-(3- hydroxyazetidin-1- yl)phenyl]-3-methyl- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 428 429 E224

ethyl 4-[4-(3- fluoroazetidin-1- yl)phenyl]-3-methyl- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 430 431 E225

ethyl 3-methyl-4-[4- (2-oxa-6- azaspiro[3.3]heptan- 6-yl)phenyl]-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 454 455 E226

ethyl 3-methyl-4-[4- [(1S,4S)-2-oxa-5- azabicyclo[2.2.1] heptan-5-yl]phenyl]-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 454 455 E227

ethyl 4-(4- acetylpiperazin-1- yl)-3-methyl-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate HP13 I3 407 408 E228

ethyl 4-[4-[2- (hydroxymethyl) morpholin-4-yl] phenyl]- 3-methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 472 473 E229

ethyl 3-methyl-4-[4- (8-oxa-3- azabicyclo[3.2.1] octan-3-yl)phenyl]-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 468 469 E230

ethyl 4-[4-(azetidin- 1-yl)phenyl]-3- methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 412 413 E231

ethyl 4-[4- (cyanomethyl) piperazin- 1-yl]-3-methyl- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E512 I18 404 405 E232

ethyl 4-(4-hydroxy- 1-piperidyl)-3- methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP13 I3 380 381 E233

ethyl 4-(1-acetyl-4- piperidyl)-3-methyl- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E327 I11B 406 407 E234

ethyl 4-[1- (cyanomethyl)-4- piperidyl]-3-methyl- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E327 I18 403 404 E235

ethyl 3-methyl-4-[4- [methyl(oxetan-3- yl)amino]phenyl]-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate E338 I19 442 443 E236

ethyl 1-[1- (cyanomethyl) pyrrolidin-3-yl]-3- isopropyl-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E328 I18 502 503 E237

ethyl 3-isopropyl-1-(1- methoxycarbonyl- pyrrolidin-3-yl)-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E328 I11B 521 522 E238

ethyl 4-(4-hydroxy- 1-piperidyl)-3- methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP13 I3 380 381 E239

ethyl 4-[4-(4- hydroxy-1- piperidyl)phenyl]-3- methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E350 I20 456 457 E240

ethyl 3-methyl-1- phenyl-4-[4- (tetrahydropyran-4- ylamino)phenyl] pyrazolo [3,4-b]pyridine- 6-carboxylate E010 I10 46 457 E241

ethyl 3-methyl-4-(4- methylsulfonyl- piperazin-1-yl)-1- phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E512 I11A 443 444 E242

ethyl 3-[1- (cyanomethyl)azetidin- 3-yl]-4-(4- morpholinophenyl)- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E329 I18 508 509 E243

ethyl 3-methyl-4-(2- oxo-1-piperidyl)-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate HP13 I22 378 379 E244

ethyl 4-[4-(3- hydroxypyrrolidin-1- yl)phenyl]-3-methyl- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E074 I20 442 443 E245

ethyl 3-methyl-4-[4- (2-oxa-7- azaspiro[3.5]nonan- 7-yl)phenyl]-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 482 483 E246

ethyl 4-[4-[(3S)-3- cyanopyrrolidin-1- yl]phenyl]-3-methyl- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 451 452 E247

ethyl 3-methyl-1- phenyl-4- (piperidine-1- carbonyl)pyrazolo[3, 4-b]pyridine-6- carboxylate E330 Specific example 392 393 E248

ethyl 3-isopropyl-4-(4- morpholinophenyl)- 1-[1-(2,2,2- trifluoroethyl)-3- piperidyl]pyrazolo[3, 4-b]pyridine-6- carboxylate E331 I18 559 560 E249

ethyl 1-[3- (benzyloxy) cyclohexyl]- 4-[4-(morpholin- 4-yl)phenyl]-3- (propan-2-yl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate AI07 I9 582 583 E250

ethyl 3-isopropyl-1- (m-tolyl)-4- pyrrolidin-1-yl- pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 396 397 E251

ethyl 4-(3- fluoroazetidin-1-yl)- 3-isopropyl-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 396 397 E252

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3-isopropyl- 1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01, BOR1 I2A 508 509 E253

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-1- cyclohexyl-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate AMP23, ALP09 I1 500 501 E254

ethyl 1-cyclohexyl- 3-isopropyl-4-[4-[2- methoxyethyl(methyl) amino]phenyl]pyrazolo [3,4-b]pyridine- 6-carboxylate AMP23, ALP11 I1 478 479 E255

ethyl 4-(4-cyano-1- piperidyl)-3- isopropyl-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 431 432 E256

ethyl rac-1-[(1R,3R)-3- hydroxycyclohexyl]- 4-[4-(morpholin-4- yl)phenyl]-3- (propan-2-yl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E249 I20 492 493 E257

ethyl rac-1-[(1R,3S)-3- hydroxycyclohexyl]- 4-[4-(morpholin-4- yl)phenyl]-3- (propan-2-yl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E249 I20 492 493 E258

ethyl 4-[4-(4-cyano- 1-piperidyl)phenyl]- 3-isopropyl-1-(3- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate AMP10, ALP12 I1 578 579 E259

ethyl 4-(4,4-difluoro- 1-piperidyl)-3- isopropyl-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 442 443 E260

ethyl 3-isopropyl-4-(4- morpholinophenyl)- 1-(5-morpholino-3- pyridyl)pyrazolo[3,4- b]pyridine-6- carboxylate AMP81, ALP18 I1 556 557 E261

ethyl 3-isopropyl-4- (3-methoxyazetidin- 1-yl)-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 408 409 E262

ethyl 4-[4- (hydroxymethyl)-1- piperidyl]-3- isopropyl-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 436 437 E263

ethyl 3-isopropyl-1- (m-tolyl)-4-[3- (trifluoromethyl) pyrrolidin-1- yl]pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 459 460 E264

ethyl 4-(5-tert- butoxycarbonyl- 1,3,3a,4,6,6a- hexahydropyrrolo[3, 4-c]pyrrol-2-yl)-3- isopropyl-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 533 534 E265

ethyl 4-(3- cyanopyrrolidin-1- yl)-3-isopropyl-1- (m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 417 418 E266

ethyl 4-[4-(4-cyano- 1-piperidyl)phenyl]- 3-isopropyl-1-(3- pyrrolidin-1- ylphenyl)pyrazolo[3, 4-b]pyridine-6- carboxylate AMP11, ALP12 I1 562 563 E267

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3-isopropyl- 1-(3-pyrrolidin-1- ylphenyl)pyrazolo[3, 4-b]pyridine-6- carboxylate AMP11, ALP09 I1 563 564 E268

ethyl 4-[2- (cyanomethyl)- 1,3,3a,4,6,6a- hexahydropyrrolo[3, 4-c]pyrrol-5-yl]-3- isopropyl-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate E332 I18 472 473 E269

ethyl 1-(4-chloro-2- pyridyl)-3-isopropyl- 4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate AMP82, ALP18 I1 556 557 E270

ethyl 3-isopropyl-4- [2-[2- methoxyethyl(methyl) amino]pyrimidin-5- yl]-1-(3- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate AMP10, ALP16 I1 556 557 E271

ethyl 3-isopropyl-4- [2- [methyl (tetrahydropyran-4- yl)amino]pyrimidin- 5-yl]-1-(3- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate AMP10, ALP13 I1 585 586 E272

methyl 4-{4-[4- (cyanomethyl) piperazin- 1-yl]phenyl}-1- (3-methoxyphenyl)- 3-methyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E333 I18 496 497 E273

ethyl 4-(5-acetyl- 1,3,3a,4,6,6a- hexahydropyrrolo[3, 4-c]pyrrol-2-yl)-3- isopropyl-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate E332 I11B 475 476 E274

ethyl 4-(1-tert- butoxycarbonyl- 3,3a,4,6,7,7a- hexahydro-2H- pyrrolo[3,2- c]pyridin-5-yl)-3- isopropyl-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 547 548 E275

ethyl 1-(3- fluorophenyl)-3- isopropyl-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E334 I4 488 489 E276

ethyl 1-(3,5- difluorophenyl)-3- isopropyl-4-[4- [methyl (tetrahydropyran-4- yl)amino]phenyl] pyrazolo[3,4- b]pyridine-6- carboxylate AMP09, ALP15 I1 534 535 E277

ethyl 1-(3,5- difluorophenyl)-3- isopropyl-4-[6- [methyl (tetrahydropyran- 4-yl)amino]-3- pyridyl]pyrazolo[3,4- b]pyridine-6- carboxylate AMP09, ALP10 I1 535 536 E278

ethyl 4-[4-(4-cyano- 1-piperidyl)phenyl]- 3-cyclobutyl-1-(3- pyrrolidin-1- ylphenyl)pyrazolo[3, 4-b]pyridine-6- carboxylate AMP34, ALP12 I1 574 575 E279

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3- cyclobutyl-1-(3- pyrrolidin-1- ylphenyl)pyrazolo[3, 4-b]pyridine-6- carboxylate AMP34, ALP09 I1 575 576 E280

ethyl 3-isopropyl-4- [6-[methyl (tetrahydropyran- 4-yl)amino]-3- pyridyl]-1-(3- pyrrolidin-1- ylphenyl)pyrazolo[3, 4-b]pyridine-6- carboxylate AMP11, ALP10 I1 568 569 E281

ethyl 3-cyclobutyl-4- [6-[methyl (tetrahydropyran- 4-yl)amino]-3- pyridyl]-1-(3- pyrrolidin-1- ylphenyl)pyrazolo[3, 4-b]pyridine-6- carboxylate AMP34, ALP10 I1 580 581 E282

ethyl 3-isopropyl-4- [6-[2- methoxyethyl(methyl) amino]-3-pyridyl]- 1-(3-pyrrolidin-1- ylphenyl)pyrazolo[3, 4-b]pyridine-6- carboxylate AMP11, ALP08 I1 542 543 E283

ethyl 1-cyclohexyl- 3-isopropyl-4-[4- [methyl (tetrahydropyran-4- yl)amino]phenyl] pyrazolo[3,4- b]pyridine-6- carboxylate AMP23, ALP15 I1 504 505 E284

ethyl 4-(1-acetyl- 3,3a,4,6,7,7a- hexahydro-2H- pyrrolo[3,2- c]pyridin-5-yl)-3- isopropyl-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate E349 I11B 489 490 E285

ethyl 4-[1- (cyanomethyl)- 3,3a,4,6,7,7a- hexahydro-2H- pyrrolo[3,2- c]pyridin-5-yl]-3- isopropyl-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate E349 I18 486 487 E286

ethyl 3-isopropyl-1- (m-tolyl)-4-(7-oxa-2- azaspiro[3.5]nonan- 2-yl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 448 449 E287

ethyl 4-[2-(4-cyano- 1- piperidyl)pyrimidin- 5-yl]-3-isopropyl-1- (3-pyrrolidin-1- ylphenyl)pyrazolo[3, 4-b]pyridine-6- carboxylate AMP11, ALP17 I1 564 565 E288

ethyl 4-(4-cyano-1- piperidyl)-1- cyclohexyl-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP04 I3 423 424 E289

ethyl 1-cyclohexyl- 3-isopropyl-4-(1- piperidyl)pyrazolo[3, 4-b]pyridine-6- carboxylate HP04 I3 398 399 E290

ethyl 1-cyclohexyl- 4-[4- (hydroxymethyl)-1- piperidyl]-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP04 I3 428 429 E291

ethyl 1-(3,5- difluorophenyl)-3- isopropyl-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E334 I4 506 507 E292

ethyl 1-[3- (dimethylamino) phenyl]-3-isopropyl-4- [3-(trifluoromethyl) pyrrolidin-1- yl]pyrazolo[3,4- b]pyridine-6- carboxylate HP03 I3 489 490 E293

ethyl 3-isopropyl-4-(3- methylsulfonyl- pyrrolidin- 1-yl)-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 470 471 E294

ethyl 4-(2- azaspiro[3.3]heptan- 2-yl)-3-isopropyl-1- (m-tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 418 419 E295

ethyl 3-isopropyl-1- (m-tolyl)-4-(5-oxa-2- azaspiro[3.5]nonan- 2-yl)pyrazolo[3,4- b]pyridine-6- carboxylate HP01 I3 448 449 E296

ethyl 3-cyclobutyl-4- [2-[methyl (tetrahydropyran-4- yl)amino]pyrimidin- 5-yl]-1-(3- pyrrolidin-1- ylphenyl)pyrazolo[3, 4-b]pyridine-6- carboxylate AMP34, ALP13 I1 581 582 E297

ethyl 1-(3,4- difluorophenyl)-3- isopropyl-4-[4- [methyl (tetrahydropyran-4- yl)amino]phenyl] pyrazolo[3,4- b]pyridine-6- carboxylate AMP83, ALP15 I1 534 535 E298

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-1-(3,4- difluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate AMP83, ALP09 I1 530 531 E299

ethyl 3-isopropyl-4- [2-[methyl (tetrahydropyran-4- yl)amino]pyrimidin- 5-yl]-1-[3- (trifluoromethyl) phenyl]pyrazolo[3,4- b]pyridine-6- carboxylate AMP84, ALP13 I1 568 569 E300

ethyl 1-(3- fluorophenyl)-3- isopropyl-4-[4- [methyl (tetrahydropyran-4- yl)amino]phenyl] pyrazolo[3,4- b]pyridine-6- carboxylate AMP12, ALP15 I1 516 517 E301

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-1-(3- fluorophenyl)-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate AMP12, ALP09 I1 512 513 E302

ethyl 1-(3- fluorophenyl)-3- isopropyl-4-[2- [methyl (tetrahydropyran-4- yl)amino]pyrimidin- 5-yl]pyrazolo[3,4- b]pyridine-6- carboxylate AMP12, ALP13 I1 518 519 E303

ethyl 1-(3,5- difluorophenyl)-3- isopropyl-4-[2- [methyl (tetrahydropyran-4- yl)amino]pyrimidin- 5-yl]pyrazolo[3,4- b]pyridine-6- carboxylate AMP09, ALP13 I1 536 537 E304

ethyl 1-[3- (dimethylamino) phenyl]-4-[4- (hydroxymethyl)-1- piperidyl]-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP03 I3 465 466 E305

ethyl 3-cyclobutyl-1- (3-fluorophenyl)-4- (4-morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E335 I4 500 501 E306

ethyl 3-cyclobutyl-1- (3,4-difluorophenyl)- 4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E335 I4 518 519 E307

ethyl 1-cyclohexyl- 3-isopropyl-4-(1- methylpyrrol-3- yl)pyrazolo[3,4- b]pyridine-6- carboxylate HP04 I2A 394 395 E308

ethyl 1-cyclohexyl- 4-(1,3- dimethylpyrazol-4- yl)-3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP04 I2B 409 410 E309

ethyl 3-cyclobutyl-1- (3,5-difluorophenyl)- 4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E335 I4 518 519 E310

ethyl 3-cyclobutyl-4- (4-morpholinophenyl)- 1-[3-(trifluoromethyl) phenyl]pyrazolo[3,4- b]pyridine-6- carboxylate E335 I4 550 551 E311

ethyl 3-cyclobutyl-1- (3-fluoro-4-methyl- phenyl)-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E335 I4 514 515 E312

ethyl 3-cyclobutyl-4- (4-morpholinophenyl)- 1-[4-(trifluoromethyl) phenyl]pyrazolo[3,4- b]pyridine-6- carboxylate E335 I4 550 551 E313

ethyl 3-cyclobutyl-1- [4-(dimethylamino) phenyl]-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E335 I4 525 526 E314

ethyl 1-cyclohexyl- 3-isopropyl-4-(1- isopropylpyrazol-4- yl)pyrazolo[3,4- b]pyridine-6- carboxylate HP04 I2B 423 424 E315

ethyl 4-[2-(3-cyano-1- piperidyl)pyrimidin- 5-yl]-1-cyclohexyl- 3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP04, BOR2 I2A 501 502 E316

ethyl 1-cyclohexyl- 3-isopropyl-4-(2- methylpyrazol-3- yl)pyrazolo[3,4- b]pyridine-6- carboxylate HP04 I2B 395 396 E317

ethyl 4-(1-tert- butoxycarbonyl-3,6- dihydro-2H-pyridin- 4-yl)-1-cyclohexyl- 3-isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP04 I2B 496 497 E318

ethyl 4-[2-[(1-tert- butoxycarbonyl-4- piperidyl)-methyl- amino]pyrimidin-5- yl]-1-cyclohexyl-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP04, BOR3 I2A 605 606 E319

methyl 1-(4- fluorophenyl)-4-[4- (hydroxymethyl)-1- piperidyl]-3- isopropyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP05 I3 426 427 E320

ethyl 1-cyclohexyl- 3-isopropyl-4- (2,2,6,6-tetramethyl- 3H-pyran-4- yl)pyrazolo[3,4- b]pyridine-6- carboxylate HP04 I2B 453 454 E321

ethyl 3-(1-tert- butoxycarbonyl- pyrrolidin-3-yl)oxy- 4-[6-(4-cyano-1- piperidyl)-3- pyridyl]-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E336 I13 637 638 E322

methyl 1-(4- fluorophenyl)-3- isopropyl-4- (tetrahydropyran-4- carbonylamino) pyrazolo [3,4-b]pyridine-6- carboxylate HP05 I22 440 441 E323

methyl 4-[4- (cyanomethyl)-4- hydroxy-1- piperidyl]-3- cyclobutyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 445 446 E324

ethyl 3-methyl-1- phenyl-4-(4- piperazin-1- ylphenyl)pyrazolo[3, 4-b]pyridine-6- carboxylate E010 I10 441 442 E325

ethyl 1-(1- benzyloxycarbonyl- 4-piperidyl)-3- isopropyl-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E348 I20 477 478 E326

ethyl 3-methyl-4-[4- (morpholin-4- yl)phenyl]-1-(2-oxo- 1,2-dihydropyridin- 4-yl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate AMP71, ALP18 I1 431 432 E327

ethyl 3-methyl-1- phenyl-4-(4- piperidyl)pyrazolo[3, 4-b]pyridine-6- carboxylate E339 I21A 364 365 E328

ethyl 3-isopropyl-4-(4- morpholinophenyl)- 1-pyrrolidin-3-yl- pyrazolo[3,4- b]pyridine-6- carboxylate E340 I20 463 464 E329

ethyl 3-(azetidin-3- yl)-4-(4- morpholinophenyl)- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E341 121A 469 470 E330

6-ethoxycarbonyl-3- methyl-1-phenyl- pyrazolo[3,4- b]pyridine-4- carboxylic acid 1131-18- 6 Specific example 325 326 E331

ethyl 3-isopropyl-4-(4- morpholinophenyl)- 1-(3- piperidyl)pyrazolo[3, 4-b]pyridine-6- carboxylate E342 I20 463 464 E332

ethyl 4- (2,3,3a,4,6,6a- hexahydro-1H- pyrrolo[3,4-c]pyrrol- 5-yl)-3-isopropyl-1- (m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate E264 I21B 433 434 E333

methyl 1-(3- methoxyphenyl)-3- methyl-4-(4- piperazin-1- ylphenyl)pyrazolo[3, 4-b]pyridine-6- carboxylate E343 I10 457 458 E334

ethyl 3-isopropyl-4-(4- morpholinophenyl)- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E344 I15 394 395 E335

ethyl 3-cyclobutyl-4-(4- morpholinophenyl)- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E345 I15 406 407 E336

ethyl 4-[6-(4-cyano- 1-piperidyl)-3- pyridyl]-3-oxo-1- phenyl-2H- pyrazolo[3,4- b]pyridine-6- carboxylate 70373- 98-7 (AMP88), ALP09 I1 468 469 E337

methyl 4-[4- (cyclobutylamino) phenyl]-3-methyl-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 426 427 E338

ethyl 3-methyl-4-[4- (oxetan-3- ylamino)phenyl]-1- phenyl-pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 428 429 E339

ethyl 4-(1-tert- butoxycarbonyl-4- piperidyl)-3-methyl- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate HP13 Specific example 464 465 E340

ethyl 1-(1- benzyloxycarbonyl- pyrrolidin-3-yl)-3- isopropyl-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate AI09 I9 597 598 E341

ethyl 3-(1-tert- butoxycarbonyl- azetidin-3-yl)-4-(4- morpholinophenyl)- 1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate AMP65, ALP18 I1 569 570 E342

ethyl 1-(1- benzyloxycarbonyl- 3-piperidyl)-3- isopropyl-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate AI10 I9 611 612 E343

methyl 4-(4- bromophenyl)-1-(3- methoxyphenyl)-3- methyl-pyrazolo[3,4- b]pyridine-6- carboxylate 92721- 94-3, ALP39 I1 452 453 E344

ethyl 1-[(2,4- dimethoxyphenyl) methyl]-3-isopropyl-4- (4-morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate AMP28, ALP18 I1 544 545 E345

ethyl 3-cyclobutyl-1- [(2,4- dimethoxyphenyl) methyl]-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate AMP36, ALP18 I1 556 557 E346

ethyl 1-(3- bromophenyl)-3- isopropyl-4-[6-[2- methoxyethyl(methyl) amino]-3- pyridyl]pyrazolo[3,4- b]pyridine-6- carboxylate AMP05, ALP08 I1 552 553 E347

ethyl 1-(3- bromophenyl)-3- isopropyl-4-[4- [methyl (tetrahydropyran-4- yl)amino]phenyl] pyrazolo[3,4- b]pyridine-6- carboxylate AMP05, ALP15 I1 577 578 E348

ethyl 1-(1- benzyloxycarbonyl- 4-piperidyl)-3- isopropyl-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate AI08 I9 611 612 E349

ethyl 4-(1-acetyl- 3,3a,4,6,7,7a- hexahydro-2H- pyrrolo[3,2- c]pyridin-5-yl)-3- isopropyl-1-(m- tolyl)pyrazolo[3,4- b]pyridine-6- carboxylate E274 I21B 447 448 E350

ethyl 4-[4-(4- benzyloxy-1- piperidyl)phenyl]-3- methyl-1-phenyl- pyrazolo[3,4- b]pyridine-6- carboxylate E010 I10 546 547 E351

ethyl 3-isopropyl-1- [3-[2- methoxyethyl(methyl) amino]phenyl]-4-(4- morpholinophenyl) pyrazolo[3,4- b]pyridine-6- carboxylate E001 I8 557 558 E352

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-(4- hydroxypiperidin-1- yl)-1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP19 I3 424 425 E353

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-(4-oxopiperidin-1- yl)-1H-pyrazolo[3,4- b]pyridine-6- carboxylate E352 I23 422 423 E354

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-{4-[2- (methoxymethyl) morpholin-4- yl]piperidin-1-yl}- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 537 538 E355

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[4-(3- fluoropyrrolidin-1- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 495 496 E356

methyl 4-[4-(3- cyanoazetidin-1- yl)piperidin-1-yl]-3- cyclobutyl-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 488 489 E357

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[4-(3- methoxypyrrolidin- 1-yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 507 508 E358

methyl 3-cyclobutyl- 4-(4,4-difluoro[1,4′- bipiperidin]-1′-yl)-1- (4-fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 527 528 E359

methyl 4-[4-(2- cyanomorpholin-4- yl)piperidin-1-yl]-3- cyclobutyl-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 518 519 E360

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[4-(2-oxa-5- azabicyclo[2.2.1] heptan-5-yl)piperidin-1- yl]-1H-pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 505 506 E361

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-{4-[methyl(oxan-4- yl)amino]piperidin- 1-yl}-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 521 522 E362

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-{4-[3- (trifluoromethyl) pyrrolidin-1-yl] piperidin- 1-yl}-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 545 546 E363

methyl 4-[4-(3- cyanopyrrolidin-1- yl)piperidin-1-yl]-3- cyclobutyl-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 502 503 E364

methyl 4-(3- cyano[1,4′- bipiperidin]-1′-yl)-3- cyclobutyl-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 516 517 E365

methyl 3-cyclobutyl- 4-(3-fluoro[1,4′- bipiperidin]-1′-yl)-1- (4-fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 509 510 E366

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[4-(3- methoxyazetidin-1- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 493 494 E367

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[3- (trifluoromethyl)[1,4′- bipiperidin]-1′-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 559 560 E368

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-(3-methoxy[1,4′- bipiperidin]-1′-yl)- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 521 522 E369

methyl 3-cyclobutyl- 4-[4-(2,2- dimethylmorpholin- 4-yl)piperidin-1-yl]- 1-(4-fluorophenyl)- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 521 522 E370

methyl 3-cyclobutyl- 4-{4-[4- (ethoxycarbonyl) piperazin- 1-yl]piperidin- 1-yl}-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 564 565 E371

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[1-(propan-2- yl)octahydro-5H- pyrrolo[3,2- c]pyridin-5-yl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E514 I33 491 492 E372

methyl 3-cyclobutyl- 4-(1- cyclobutyloctahydro- 5H-pyrrolo[3,2- c]pyridin-5-yl)-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E514 I33 503 504 E373

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[1-(oxetan-3- yl)octahydro-5H- pyrrolo[3,2- c]pyridin-5-yl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E514 I33 505 506 E374

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[1-(oxan-4- yl)octahydro-5H- pyrrolo[3,2- c]pyridin-5-yl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E514 I33 533 534 E375

methyl 3-cyclobutyl- 4-(4-fluoro[1,4′- bipiperidin]-1′-yl)-1- (4-fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 509 510 E376

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-{4-[(2- methoxyethyl)(methyl) amino]piperidin- 1-yl}-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 495 496 E377

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[4-(morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP19 I3 493 494 E378

methyl 4-([1,4′- bipiperidin]-1′-yl)-3- cyclobutyl-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP19 I3 491 492 E379

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-(3-hydroxy-1-oxa- 8-azaspiro[4.5]decan- 8-yl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP19 I3 480 481 E380

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-(3-oxo-1-oxa-8- azaspiro[4.5]decan- 8-yl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E379 I23 478 479 E381

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[3-(pyrrolidin-1- yl)-1-oxa-8- azaspiro[4.5]decan- 8-yl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E380 I33 533 534 E382

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-{4-[2-(morpholin- 4-yl)ethyl]piperidin- 1-yl}-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP19 I3 521 522 E383

methyl 3-cyclobutyl- 4-{4-[2-(4- methylpiperidin-1- yl)ethyl]piperidin-1- yl}-1-phenyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 515 516 E384

methyl 3-cyclobutyl- 4-[4-(4- cyclopropylpiperazin- 1-yl)piperidin-1-yl]- 1-phenyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 514 515 E385

methyl 3-cyclobutyl- 1-phenyl-4-[4- (propan-2- yl)piperazin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 433 434 E388

ethyl 3-cyclobutyl-4- [4- (methoxymethyl) piperidin-1-yl]-1-(2- methoxypyridin-4- yl)-1H-pyrazolo[3,4- b]pyridine-6- carboxylate E168 I4 479 480 E389

ethyl 1-(2- chloropyridin-4-yl)- 3-cyclobutyl-4-[4- (methoxymethyl) piperidin-1-yl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E168 I4 484- 486 485- 487 E390

ethyl 3-cyclobutyl-1- [2-(3,6-dihydro-2H- pyran-4-yl)pyridin-4- yl]-4-[4- (methoxymethyl) piperidin-1-yl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E389 Specific example 531 532 E391

ethyl 3-cyclobutyl-4- [4- (methoxymethyl) piperidin-1-yl]-1-[2- (oxan-4-yl)pyridin-4- yl]-1H-pyrazolo[3,4- b]pyridine-6- carboxylate E390 Specific example 533 534 E392

ethyl 1-tert-butyl-3- cyclobutyl-4-[4- (morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP20 I3 469 470 E393

ethyl 3-cyclobutyl-4- [4-(morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E392 Specific example 413 414 E394

ethyl 3-cyclobutyl-1- (2-methoxypyridin- 4-yl)-4-[4- (morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E393 I4 520 521 E395

ethyl 3-cyclobutyl-1- (3-methylphenyl)-4- [4-(morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E393 I4 503 504 E396

ethyl 3-cyclobutyl-1- (3-methoxyphenyl)- 4-[4-(morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E393 I4 519 520 E397

ethyl 3-cyclobutyl-4- [4-(morpholin-4- yl)piperidin-1-yl]-1- [4-(trifluoromethyl) phenyl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E393 I4 557 558 E398

ethyl 3-cyclobutyl-1- (4-fluoro-3- methylphenyl)-4-[4- (morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E393 I4 521 522 E399

ethyl 3-cyclobutyl-4- [4-(morpholin-4- yl)piperidin-1-yl]-1- [3-(trifluoromethyl) phenyl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E393 I4 557 558 E400

ethyl 3-cyclobutyl-4- [4-(morpholin-4- yl)piperidin-1-yl]-1- {2-[(propan-2- yl)oxy]pyridin-4-yl}- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E393 I4 548 549 E401

ethyl 1-[2- (benzyloxy)pyridin- 4-yl]-3-cyclobutyl-4- [4-(morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E393 I4 596 597 E402

ethyl 3-cyclobutyl-1- (2-hydroxypyridin-4- yl)-4-[4-(morpholin- 4-yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E401 Specific example 506 507 E403

ethyl 3-cyclobutyl-1- [2-(difluoromethoxy) pyridin-4-yl]-4-[4- (morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E393 I4 556 557 E404

ethyl 3-cyclobutyl-1- (3-fluorophenyl)-4- [4-(morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E393 I4 507 508 E405

ethyl 3-cyclobutyl-1- (2,2-difluoro-2H-1,3- benzodioxol-5-yl)-4- [4-(morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E393 I4 569 570 E406

ethyl 1-(2- chloropyridin-4-yl)- 3-cyclobutyl-4-[4- (morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E393 I4 525- 527 526- 528 E407

ethyl 3-cyclobutyl-4- [4-(morpholin-4- yl)piperidin-1-yl]-1- [2-(oxan-4- yl)pyridin-4-yl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E406 Specific example 574 575 E408

methyl 3-cyclobutyl- 4-[4-(ethoxymethyl)- 4-fluoropiperidin-1- yl]-1-phenyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP02, AMI04 I3 466 467 E409

methyl 3-cyclobutyl- 4-{4-fluoro-4-[(2- methoxyethoxy)methyl] piperidin-1-yl}-1- phenyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP02, AMI05 I3 496 497 E410

methyl 3-cyclobutyl- 4-{3-fluoro-3-[(2- methoxyethoxy)methyl] piperidin-1-yl}-1- phenyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP02, AMI08 I3 496 497 E411

methyl 3-cyclobutyl- 4-[4-fluoro-4- (methoxymethyl) piperidin-1-yl]-1- phenyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP02, AMI07 I3 452 453 E412

methyl 3-cyclobutyl- 4-{4-[2-(4- methylpiperidin-1- yl)ethyl]piperidin-1- yl}-1-phenyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP02 I3 515 516 E413

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-(piperidin-4-yl)- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP19 Specific example 408 409 E414

methyl 3-cyclobutyl- 4-[1-(4,4- difluorocyclohexyl) piperidin-4-yl]-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E413 I18 526 527 E415

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[1-(propan-2- yl)piperidin-4-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E413 I18 450 451 E416

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[1-(oxan-4- yl)piperidin-4-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E413 I18 492 493 E417

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-{1-[(oxan-4- yl)methyl]piperidin- 4-yl}-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E413 I18 506 507 E418

methyl 3-cyclobutyl- 4-{1-[(2,5- dimethoxyoxolan-3- yl)methyl]piperidin- 4-yl}-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E413 I18 552 553 E419

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[1-(3,3,3- trifluoropropyl) piperidin-4-yl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E413 I18 504 505 E421

methyl 3-cyclobutyl- 4-[1- (cyclopropylmethyl) piperidin-4-yl]-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E413 I18 462 463 E422

ethyl 1-(2- chloropyrimidin-4- yl)-3-cyclobutyl-4- [4-(morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E393 I5 525 526 E424

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-(4-methoxy[1,4′- bipiperidin]-1′-yl)- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP19, AMI10 I3 521 522 E425

ethyl 1-cyclohexyl- 4-(4-formylphenyl)- 3-[(propan-2- yl)oxy]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate ALP36, AMP95 Specific example 435 436 E426

ethyl 1-cyclohexyl- 4-(4-{[3- (dimethylamino) azetidin-1- yl]methyl}phenyl)-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E425 I34 519 520 E427

ethyl 4-(4- cyanophenyl)-1- cyclohexyl-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate 436088- 86-7, ALP37 Specific example 432 433 E428

ethyl 1-(6- bromopyridin-2-yl)- 3-cyclobutyl-4-[4- (morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E393 Specific example 568- 570 569- 571 E429

methyl 1-(4- fluorophenyl)-4-(4- methoxy[1,4′- bipiperidin]-1′-yl)-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate AI25 Specific example 525 526 E430

methyl 3-cyclobutyl- 4-(1,4- dioxaspiro[4.5]dec- 7-en-8-yl)-1-phenyl- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP02 Specific example 445 446 E431

methyl 3-cyclobutyl- 4-(1,4- dioxaspiro[4.5]decan- 8-yl)-1-phenyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E430 Specific example 447 448 E432

methyl 3-cyclobutyl- 4-(4-oxocyclohexyl)- 1-phenyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E431 Specific example 403 404 E433

methyl 3-cyclobutyl- 4-[4-(morpholin-4- yl)cyclohexyl]-1- phenyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E432 I33 474 475 E434

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-{4-[4-(propan-2- yl)piperazin-1- yl]piperidin-1-yl}- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E353 I33 534 535 E435

ethyl 1-cyclohexyl- 3-[(propan-2- yl)oxy]-4-(4-{[4- (propan-2- yl)piperazin-1- yl]methyl}phenyl)- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E425 I34 547 548 E436

ethyl 1-cyclohexyl- 4-{4-[(4- methoxypiperidin-1- yl)methyl]phenyl}-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E425 I34 534 535 E437

ethyl 1-cyclohexyl- 4-{4-[(5- methylhexahydro- pyrrolo [3,4-c]pyrrol- 2(1H)- yl)methyl]phenyl}-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E425 I34 545 546 E438

4-{1-cyclohexyl-6- (ethoxycarbonyl)-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridin-4- yl}benzoic acid E425 Specific example 451 452 E439

ethyl 4-{4-[5-(tert- butoxycarbonyl) hexahydropyrrolo[3,4- c]pyrrole-2(1H)- carbonyl]phenyl}-1- cyclohexyl-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E438 I24 645 646 E440

ethyl 1-cyclohexyl- 4-[4-(5- methylhexahydro- pyrrolo[3,4-c]pyrrole- 2(1H- carbonyl)phenyl]-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E438 I24 559 560 E441

ethyl 1-cyclohexyl- 4-{4-[3- (dimethylamino) azetidine-1- carbonyl]phenyl}-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E438 I24, Specific example 533 534 E442

ethyl 4-(4-{[8-(tert- butoxycarbonyl)-2- oxa-5,8- diazaspiro[3.5]nonan- 5-yl]methyl}phenyl)-1- cyclohexyl-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E425 I34 647 648 E443

ethyl 1-cyclohexyl- 4-{4-[(2-oxa-5,8- diazaspiro[3.5]nonan- 5-yl)methyl]phenyl}-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E442 I21A 547 548 E444

ethyl 1-cyclohexyl- 4-{4-[(8-methyl-2- oxa-5,8- diazaspiro[3.5]nonan- 5-yl)methyl]phenyl}-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E443 Specific example 561 562 E445

ethyl 4-[4-(4-cyano- 1-methylpiperidin-4- yl)phenyl]-1- cyclohexyl-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate ALP38, AMP 95 Specific example 529 530 E460

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-{4-[1-(morpholin- 4-yl)ethyl]piperidin- 1-yl}-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP19, 436852- 25-4 I3 521 522 E461

methyl 3-cyclobutyl- 1-cyclohexyl-4-[4- (2-methylpyridin-4- yl)piperazin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP25, 98010- 38-9 I3 488 489 E462

methyl 3-cyclobutyl- 1-cyclohexyl-4-{4- [4-(propan-2- yl)piperazin-1- yl]piperidin-1-yl}- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP25, 202991- 78-4 I3 522 523 E463

methyl 4-[(3S)-4- benzyl-3- methylpiperazin-1- yl]-3-cyclobutyl-1- cyclohexyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP25, 511254- 92-57 I3 501 502 E464

methyl 4-[(3R)-4- benzyl-3- methylpiperazin-1- yl]-3-cyclobutyl-1- cyclohexyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP25, 1588480- 39-0 I3 501 502 E465

methyl 3-cyclobutyl- 4-[4-(4- cyclopropylpiperazin- 1-yl)piperidin-1-yl]- 1-(4-fluorophenyl)- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E496 I26 517 518 E466

methyl 3-cyclobutyl- 4-(9-cyclopropyl- 3,9-diazaspiro[5.5] undecan-3-yl)-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E500 I26 517 518 E467

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-{4-[(pyrrolidin-1- yl)methyl]piperidin- 1-yl}-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP19, 683772- 11-5 I3 491 492 E468

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-{4-[4-(2- methoxyethyl) piperazin- 1-yl]piperidin-1- yl}-1H-pyrazolo[3,4- b]pyridine-6- carboxylate E496, 6482-24- 2 I27 550 551 E469

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[9-(oxetan-3-yl)- 3,9-diazaspiro[5.5] undecan-3-yl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E500, 6704-31- 0 I30 533 534 E470

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-{4-[4-(oxetan-3- yl)piperazin-1- yl]piperidin-1-yl}- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E496, 6704-31- 0 I30 548 549 E471

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[(morpholin-4- yl)methyl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP19, 936329- 94-1 I35 424 425 E472

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[(4- methylpiperazin-1- yl)methyl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP19, 1015484- 22-6 I35 438 439 E473

methyl 1-cyclohexyl- 4-{4-[(morpholin-4- yl)methyl]phenyl}-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E506, 1268340- 94-8 I35 493 493 E474

methyl 1-cyclohexyl- 4-[4-(4- methylpiperazine-1- carbonyl)phenyl]-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E506, 34352- 59-5 I28 519 520 E475

methyl 3-cyclobutyl- 1-cyclohexyl-4-[4- (pyridin-4- yl)piperazin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP25, 1008-91- 9 I3 474 475 E476

methyl 3- (cyclobutyloxy)-1- cyclohexyl-4-{4- [(morpholin-4- yl)methyl]phenyl}- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E507, 1268340- 94-8 I35 504 505 E477

methyl 1-cyclohexyl- 4-{4-[4- (dimethylamino) piperidine-1- carbonyl]phenyl}-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E506, 4318-42- 7 I28 548 549 E478

methyl 1-cyclohexyl- 4-{4-[(piperidin-1- yl)methyl]phenyl}-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E506, 1268340- 93-7 I35 491 492 E479

methyl 1-cyclohexyl- 4-{4-[(4- methylpiperazin-1- yl)methyl]phenyl}-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E506, 1015484- 22-6 I35 506 507 E480

methyl 1-cyclohexyl- 3-[(propan-2- yl)oxy]-4-{4- [(pyrrolidin-1- yl)methyl]phenyl}- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E506, 888711- 53-3 I35 477 477 E481

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-{[4- (methoxymethyl) piperidin-1-yl]methyl}- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP19, BF01 I35 466 467 E482

methyl 1-cyclohexyl- 4-{4-[(4- cyclopropylpiperazin- 1-yl)methyl]phenyl}-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E494 I26 531 532 E483

methyl 1-cyclohexyl- 3-[(propan-2- yl)oxy]-4-{4-[4- (propan-2- yl)piperazin-1- yl]phenyl}-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E506, 4318-42- 7 I29 519 520 E484

methyl 1-cyclohexyl- 4-[4-(4- cyclopropylpiperazin- 1-yl)phenyl]-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E506, 20327- 23-5 I29 517 518 E485

methyl 4-(4- cyano[1,4′- bipiperidin]-1′-yl)-3- cyclobutyl-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP19, AMI11 I3 516 517 E486

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-{4-[4- (methoxycarbonyl) piperazin-1- yl]piperidin-1-yl}- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E498 I31 550 551 E487

methyl 4-[4-(4- acetylpiperazin-1- yl)piperidin-1-yl]-3- cyclobutyl-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E498 I32 534 535 E488

methyl 3-cyclobutyl- 1-cyclohexyl-4-{4- [(morpholin-4- yl)methyl]piperidin- 1-yl}-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP25, 81310- 62-5 I3 495 496 E489

methyl 3-cyclobutyl- 1-cyclohexyl-4-{4- [2-(morpholin-4- yl)ethyl]piperidin-1- yl}-1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP25, 500357- 64-2 I3 509 510 E490

methyl 3-cyclobutyl- 1-cyclohexyl-4-[4- (morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP25, 53617- 35-9 I3 481 482 E491

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-{4-[(morpholin-4- yl)methyl]piperidin- 1-yl}-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP19, 202991- 78-4 I3 507 508 E492

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-(4-hydroxy[1,4′- bipiperidin]-1′-yl)- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP19, 202991- 78-4 I3 507 508 E494

methyl 1-cyclohexyl- 4-{4-[(piperazin-1- yl)methyl]phenyl}-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E495 I25 491 492 E495

methyl 4-(4-{[4- (tert- butoxycarbonyl) piperazin-1- yl]methyl}phenyl)-1- cyclohexyl-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E506, 936329- 97-4 I35 591 592 E496

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[4-(piperazin-1- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E497 I25 492 493 E497

methyl 4-{4-[4-(tert- butoxycarbonyl) piperazin-1- yl]piperidin- 1-yl}-3-cyclobutyl- 1-(4-fluorophenyl)- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP19, 205059- 24-1 I3 592 593 E498

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[4-(piperazin-1- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E499 I25 492 493 E499

methyl 4-{4-[4-(tert- butoxycarbonyl) piperazin-1- yl]piperidin- 1-yl}-3-cyclobutyl- 1-(4-fluorophenyl)- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP19, 205059- 24-1 I3 592 593 E500

methyl 3-cyclobutyl- 4-(3,9- diazaspiro[5.5] undecan-3-yl)-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E501 I25 477 478 E501

tert-butyl 9-[3- cyclobutyl-1-(4- fluorophenyl)-6- (methoxycarbonyl)- 1H-pyrazolo[3,4- b]pyridin-4-yl]-3,9- diazaspiro[5.5] undecane-3-carboxylate HP19 173405- 78-2 I3 577 578 E502

methyl 1-cyclohexyl- 4-[4-(4- methylpiperazin-1- yl)phenyl]-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E506, 109-01-3 I29 491 492 E503

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[9-(2- methoxyethyl)-3,9- diazaspiro[5.5] undecan-3-yl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E500, 6482-24- 2 I27 535 536 E504

methyl 3-cyclobutyl- 4-(9-cyclobutyl-3,9- diazaspiro[5.5] undecan-3-yl)-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E500, 1191-95- 3 I33 531 532 E505

methyl 4-(4- bromophenyl)-1- cyclohexyl-3- hydroxy-1H- pyrazolo[3,4- b]pyridine-6- carboxylate 436088- 86-7, 608128- 34-3 I1, Specific example 430 E506

methyl 4-(4- bromophenyl)-1- cyclohexyl-3- [(propan-2-yl)oxy]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E505, 75- 26-3 I17, Specific example 472 E507

methyl 4-(4- bromophenyl)-3- (cyclobutyloxy)-1- cyclohexyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E505, 4399-47- 4 I17, Specific example 484 E508

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-[9-(propan-2-yl)- 3,9-diazaspiro[5.5] undecan-3-yl]-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E500, 67-64-1 I30 519 520 E509

methyl 3-cyclobutyl- 4-[4-(morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate 53617- 35-9, 16063- 69-7, 5006-22- 4, 301-01-2, 630-08-0 Specific example 399 400 E510

methyl 3-cyclobutyl- 1-[3- (difluoromethoxy) phenyl]-4-[4- (morpholin-4- yl)piperidin-1-yl]- 1H-pyrazolo[3,4- b]pyridine-6- carboxylate E509 Specific example 541 542 E511

ethyl 4-[4-(tert- butoxycarbonyl) piperazin-1-yl]-3- methyl-1-phenyl-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP13 I3 465 466 E512

ethyl 3-methyl-1- phenyl-4-(piperazin- 1-yl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E511 I21B 365 366 E513

methyl 4-[1-(tert- butoxycarbonyl) octahydro-5H- pyrrolo[3,2- c]pyridin-5-yl]-3- cyclobutyl-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylatee HP19 I3 549 550 E514

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-(octahydro-5H- pyrrolo[3,2- c]pyridin-5-yl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate E513 I21A 449 450 E515

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-(9-methyl-3,9- diazaspiro[5.5] undecan-3-yl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP19, 13323- 45-0 I3 491 492 E516

methyl 3-cyclobutyl- 4-[4- (ethoxycarbonyl) piperazin-1-yl]-1-(4- fluorophenyl)-1H- pyrazolo[3,4- b]pyridine-6- carboxylate HP19, 120-43-4 I3 481 482 E517

methyl 3-cyclobutyl- 1-(4-fluorophenyl)- 4-{4-[(2- methylpropoxy) carbonyl]piperazin-1- yl}-1H-pyrazolo[3,4- b]pyridine-6- carboxylate HP19, 23672- 96-0 I3 509 510

Methods J1-22: Synthesis of Carboxylic Acids Method J1: Synthesis of Carboxylic Acids by Saponification of Ester

To the intermediate ester (1 equiv) in THF or in a mixture of THF/methanol or in dioxane/water at RT is added either aqueous 1-2 N sodium hydroxide or lithium hydroxide monohydrate (from 1 to 5 equiv). The reaction mixture is stirred at a temperature ranging from RT to 70° C. for 1 hour to several days (up to 8 days). The volatiles are removed under reduced pressure, and the resulting mixture is acidified with either aqueous 1-2 N HCl or acetic acid. If a filterable suspension is obtained, the precipitate is collected by filtration, washed with water and dried in vacuo to afford the titled compound which is used as such or further purified either by preparative HPLC or flash chromatography on silica gel. In other cases, the mixture is partitioned between water and either dichloromethane or ethyl acetate. The two phases are separated, and the aqueous phase is extracted either with dichloromethane, methanol/dichloromethane or ethyl acetate. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the titled compound which is used as such or further purified either by preparative HPLC or flash chromatography on silica gel.

Illustrative synthesis of compound 182: 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Intermediate E018 (30.7 g, 60.3 mmol) was dissolved in a mixture of THF/methanol (1/1; 1 L), and 2 N sodium hydroxide (109 mL, 218 mmol) in water was added at RT. The solution was stirred for 1 hour. The volatiles were removed under reduced pressure, and the resulting mixture was diluted with water (300 mL). The aqueous phase was acidified with aqueous 2 N HCl (110 mL), and the precipitate was filtered, washed with water and dried at 40° C. under reduced pressure to give the titled compound.

Method J1A: Synthesis of Carboxylic Acids by Saponification of Ester

To the ester intermediate (1 equiv) in THF or ethanol or methanol or a mixture of the cited solvents at RT is added either aqueous 1 N or 2 N sodium hydroxide 1 (from 1 to 10 equiv). The reaction mixture is stirred at RT until complete conversion is observed. Sodium hydroxide can be added to allow the full conversion of the starting ester. The volatiles are removed under reduced pressure, and the resulting mixture is acidified with either aqueous 1 N or 2 N HCl. If a filterable suspension is obtained, the precipitate is collected by filtration, washed with water and dried in vacuo to afford the titled compound which is used as such or further purified either by preparative HPLC or flash chromatography on silica gel. In other cases, the mixture is partitioned between a phosphate buffer (pH 6.2) and either dichloromethane or chloroform or a mixture of dichloromethane/isopropanol. The organic phases are separated, dried over MgSO₄, filtered and concentrated in vacuo to afford the titled compound which is used as such or further purified either by preparative HPLC or flash chromatography on silica gel.

Illustrative synthesis of compound 820: 3-cyclobutyl-1-(3-methylphenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Ester E395 (40 mg, 80 μmol) was dissolved in a mixture of THF/ethanol (1/1; 6 mL) and 1 N sodium hydroxide (0.5 mL, 500 μmol) in water was added at RT. The solution was stirred for 4 hours. Aqueous 1 N HCl (0.5 mL, 500 μmol) and a phosphate buffer were added (pH 6.2).

The solvent was partially removed under reduced pressure, and the resulting mixture was extracted twice with chloroform. The combined organic phases were dried over magnesium sulfate, filtered and evaporated under reduced pressure to give the titled compound.

Method J2: Synthesis of Acids

-   A is either N or CH -   A′ is either R^(e) or L¹-G^(3C) as described in the Summary

The alkylidene pyruvate (1 to 1.5 equiv) and the aminopyrazole (1 to 1.5 equiv) in acetic acid are stirred under air at temperatures ranging from RT to reflux for 1 h to several days. Alternatively, the alkylidene pyruvate (1 to 1.5 equiv) and the aminopyrazole (1 to 1.5 equiv) in DMF or acetic acid are heated under microwave irradiation at 150° C. for 20 minutes to 2 h followed by stirring under air in an opened flask at temperatures ranging from RT to 90° C. for 1 h to several days with or without dilution of the reaction mixture with a large amount of ethanol or methanol. Then the reaction mixture is filtered, and the solid is washed with solvents, and dried in vacuo to afford the titled compound which is used as such or purified by precipitation, by preparative HPLC or by flash chromatography on silica gel. Alternatively, the reaction mixture is concentrated in vacuo to afford a crude mixture which is used as such or further purified either by precipitation, by preparative HPLC or by flash chromatography on silica gel.

Illustrative synthesis of compound 1: 3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

ALP01 (261 mg, 1 mmol, 1 equiv) and 3-methyl-1-phenyl-1H-pyrazol-5-amine (CAS 1131-18-6, 173 mg, 1 mmol, 1 equiv) were introduced in a sealed tube. DMF (2 mL) was added, and the vial was sealed. The reaction mixture was heated under microwave irradiation at 150° C. for 1 h. Then after cooling down to RT, the vial was opened, diluted with a large amount of ethanol, and stirred vigorously under air at RT overnight. The resulting suspension was filtered. The solid was washed with ethanol, and dried in vacuo to afford the titled compound.

Method J3: Nucleophilic Substitution on the Central Core with Alcohols

To a solution of alcohol (3.0-4.0 equiv) in anhydrous THF under nitrogen atmosphere at RT is added 60% sodium hydride in mineral oil (6.0 equiv), and the mixture is stirred at room temperature for 30 minutes. Then the aryl chloride intermediate HP (1.0 equiv) is added, the reaction mixture is stirred at room temperature for 5 minutes, and then heated at reflux for 1 h to 24 h. The reaction mixture is cooled to 0° C., diluted with heptane, quenched with water and acidified with 2 N HCl (6.0 equiv). Volatiles are removed in vacuo. The resulting aqueous residue is filtered, and the solid is washed with water and with a mixture of heptane/Et₂O (1/1), and dried in vacuo to afford the titled compound which is used as such or purified by silica gel chromatography. Alternatively, the aqueous residue is diluted with dichloromethane. The two phases are separated and the aqueous phase is extracted with dichloromethane. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the titled compound which is used as such or purified by silica gel chromatography. As another alternative, the compounds can be purified by preparative HPLC.

Alternatively, to a solution of alcohol (2.0 equiv) in anhydrous DMF is added 1 M potassium tert-butoxide (3-4 equiv), and the mixture is stirred at room temperature for several minutes. Then the aryl chloride intermediate HP (1.0 equiv) is added, and then the reaction mixture is heated at 40-60° C. for 1 h to 24 h. After cooling to ambient temperature, the product can be precipitated from an appropriate solvent or purified chromatographically.

Illustrative synthesis of compound 417: 3-cyclobutyl-4-[(oxan-4-yl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

To a solution of tetrahydropyran-4-ylmethanol (CAS: 14774-37-9, 54 mg, 0.457 mmol, 3.0 equiv) in anhydrous THF (1 mL) under nitrogen atmosphere was added 60% sodium hydride in mineral oil (37 mg, 0.915 mmol, 6.0 equiv), and the mixture was stirred at room temperature for 30 minutes. HP10 (50 mg, 0.152 mmol, 1.0 equiv) was added; the reaction mixture was stirred at room temperature for 5 minutes and then heated at reflux for 3 hours. The reaction mixture was cooled to 0° C., diluted with heptane (1 mL), quenched with water (1 mL) and acidified with 2 N HCl (0.46 mL, 6.0 equiv). Volatiles were removed in vacuo. The resulting aqueous suspension was diluted with a mixture heptane/Et₂O: 1/1 (1 mL) and filtered. The solid was washed with water and with a mixture heptane/Et₂O 1/1 and dried in vacuo. The crude solid was purified by silica gel chromatography (eluent system: DCM/(DCM/MeOH/AcOH/H₂O: 90/10/1/1) gradient from 100/0 to 90/10) to give the titled compound.

Illustrative synthesis of compound 487: 3-cyclobutyl-4-[3-(morpholin-4-yl)propoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

3-Morpholinopropan-1-ol (73 mg, 0.50 mmol) was dissolved into anhydrous DMF (830 μL), treated with 1 M KOtBu in THF (830 μL, 0.83 mmol), stirred three minutes, treated further with intermediate HP10 (82 mg, 0.25 mmol), and heated at 50° C. for about an hour. More DMF (570 μL) was added and heating was continued overnight. The mixture was brought to room temperature, diluted with MeCN and filtered with a MeCN rinse. The collected solids were mixed with acetic acid into DMSO, and diluted with water to precipitate solids which were collected by filtration, rinsed with water and dried under vacuum to give the titled compound (65 mg).

Illustrative synthesis of compound 375: 3-methyl-4-[(3-methyloxetan-3-yl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

To a 4-mL vial equipped with stir bar was added (3-methyloxetan-3-yl)methanol (50 mg, 4 equiv, 0.5 mmol) followed by sodium hydride (20 mg, 6 equiv, 0.73 mmol) in 500 μL of THF, and the mixture was allowed to stir for 30 minutes at room temperature. To this mixture was then added a solution of 4-chloro-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid (HP17, 35 mg, 0.12 mmol) in 500 μL THF, and this mixture was heated at 80° C. for 30 minutes. After completion of reaction, the mixture was concentrated and the residue was dissolved in 1:1 MeOH:DMSO and purified by reverse phase HPLC (C18, 0-100% CH₃CN/water (0.1% TFA)). A gradient of acetonitrile (A) and 0.1% trifluoroacetic acid in water (B) was used, at a flow rate of 50 mL/min (0-0.5 min 10% A, 0.5-6.0 min linear gradient 10-100% A, 6.0-7.0 min 100% A, 7.0-8.0 min linear gradient 100-10% A) to afford the titled compound.

Method J4: Buchwald Coupling on the Central Core

To a degassed solution of the aryl chloride intermediate HP (1.0 equiv) and the amine as free base or hydrochloride salt (1.5 equiv) in anhydrous THF at RT under nitrogen atmosphere in a sealed vial is added XPhos Pd G1 (CAS 1028206-56-5, 0.1 equiv) followed by 1 N LiHMDS in THF (from 3 to 5 equiv). The reaction mixture is purged with nitrogen and the vial is sealed. The reaction mixture is stirred at 100° C. for 1 h to 24 h. Then the reaction mixture is cooled down and volatiles are removed in vacuo. The resulting residue is taken up in dichloromethane and water and acidified with acetic acid. The two phases are separated and the aqueous phase is extracted with dichloromethane. The combined organic layers are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue is purified by flash chromatography on silica gel to afford the titled compound.

Illustrative synthesis of intermediate AI13: 3-cyclobutyl-4-[4-(fluoromethyl)-1-piperidyl]-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylic acid

To a degassed solution of HP10 (64 mg, 0.194 mmol, 1.0 equiv) and 4-(fluoromethyl)piperidine hydrochloride (CAS 259143-04-9, 45 mg, 0.292 mmol, 1.5 equiv) in anhydrous THF (2 mL) at RT under nitrogen atmosphere in a sealed vial was added XPhos Pd G1 (CAS 1028206-56-5, 14 mg, 0.019 mmol, 0.1 equiv) followed by 1 N LiHMDS in THF (0.97 mL, 0.97 mmol, 5.0 equiv). The reaction mixture was purged with nitrogen, and the vial was sealed. The reaction mixture was stirred at 100° C. overnight. Then the reaction mixture was cooled down and volatiles were removed in vacuo. The resulting residue was taken up in dichloromethane and water and acidified with acetic acid. The two phases were separated, and the aqueous phase was extracted with dichloromethane. The combined organic layers were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue was purified by flash chromatography on silica gel (eluent system: dichloromethane/methanol gradient from 100/0 to 95/5) to afford the titled compound.

Method J5: Buchwald Coupling on the Aryl Linker

To a degassed solution of pyridyl chloride (1.0 equiv) and amine (1.5 equiv) in anhydrous THF at RT under nitrogen atmosphere is added 1 N LiHMDS in THF (from 3 to 4.5 equiv) followed by XPhos Pd G1 (CAS 1028206-56-5, 0.1 equiv). The reaction mixture is stirred at room temperature for 1 h to 24 h. The mixture is quenched with acetic acid and diluted with water and dichloromethane. The organic layer is separated, washed with water and brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the titled compound which is used as such or further purified by preparative HPLC or by flash chromatography on silica gel. The cross-coupling reaction can be performed on either a carboxylic acid or ester. In some instances, an ester starting material is concomitantly hydrolyzed to the corresponding carboxylic acid product under the reaction conditions.

Illustrative synthesis of compound 196: 1-cyclohexyl-4-[6-(2,6-dimethylmorpholin-4-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

To a degassed solution of AI14 (75 mg, 0.188 mmol, 1.0 equiv) and 2,6-dimethylmorpholine (CAS 141-91-3, 32 μL, 0.26 mmol, 1.5 equiv) in anhydrous THF (0.7 mL) at RT under nitrogen atmosphere was added 1 N LiHMDS in THF (765 μL, 0.765 mmol, 4.5 equiv) followed by XPhos Pd G1 (CAS 1028206-56-5, 12.5 mg, 0.017 mmol, 0.1 equiv). The reaction mixture was stirred at room temperature for 1 h. The mixture was quenched with AcOH and diluted with water and dichloromethane. The organic layer was separated, washed with water and brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue was purified by silica gel chromatography (eluent system: dichloromethane/methanol, gradient from 100/0 to 95/5) to afford the titled compound.

Method J6: Nucleophilic Substitution on the R¹ Part

To the intermediate fluoropyridine (1.0 equiv) in anhydrous DMSO is added the amine (from 2.0 to 10.0 equiv) and K₂CO₃ (from 3.0 to 10 equiv). The reaction mixture is stirred at 100° C. overnight. If the reaction is not complete, additional amine (from 2.0 to 10 equiv) and K₂CO₃ (from 0 to 10 equiv) are added, and the reaction mixture is stirred at 100° C. until the reaction is finished. Then the reaction mixture is cooled down to RT, diluted with water and extracted with ethyl acetate. The combined organic layers are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the titled compound which is used as such or purified by flash chromatography on silica gel.

Illustrative synthesis of compound 525: 4-[4-(methoxymethyl)piperidin-1-yl]-1-[2-(morpholin-4-yl)pyridin-4-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

To E147 (144 mg, 0.32 mmol, 1.0 equiv) in anhydrous DMSO (1.5 mL) was added morpholine (56 μL, 0.64 mmol, 2.0 equiv) and K₂CO₃ (133 mg, 0.96 mmol, 3.0 equiv). The reaction mixture was stirred at 100° C. overnight. Additional morpholine (56 μL, 0.64 mmol, 2.0 equiv) and K₂CO₃ (133 mg, 0.96 mmol, 3.0 equiv) were added, and the reaction mixture was stirred at 100° C. for 24 h. Then additional morpholine (56 μL, 0.64 mmol, 2.0 equiv) was added again, and the reaction mixture was stirred at 100° C. for 5 days. Then the reaction mixture was cooled down to RT, diluted with water and extracted with ethyl acetate. The combined organic layers were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue was purified by silica gel chromatography (eluent system: dichloromethane/methanol, gradient 100/0 to 95/5 with 0.1% AcOH) to afford the titled compound.

Method J7: Buchwald Coupling on the Phenyl or Heteroaryl Halogen

To a degassed solution of the aromatic bromide intermediate (1.0 equiv) and the amine as free base or hydrochloride salt (from 1.5 to 2 equiv) in anhydrous THF at RT under nitrogen atmosphere in a sealed vial is added XPhos Pd G1 (CAS 1028206-56-5, 0.1 equiv) followed by 1 N LiHMDS in THF (from 3 to 5 equiv). The reaction mixture is purged with nitrogen, and the vial is sealed. The reaction mixture is stirred at a temperature ranging from RT to 100° C. for 1 h to 3 h. If the reaction is not complete, additional amine (from 1.0 to 3.0 equiv), LiHMDS (from 1.5 to 6.0 equiv) and XPhos Pd G1 (CAS 1028206-56-5, from 0.05 to 0.2 equiv) are added at RT. The reaction mixture is purged again with nitrogen and the vial is sealed. The reaction mixture is stirred at a temperature ranging from RT to 100° C. for 1 h to 3 h. Then the reaction mixture is cooled down and volatiles are removed in vacuo. The resulting residue is taken up in dichloromethane and water and acidified with acetic acid. The two phases are separated, and the aqueous phase is extracted with dichloromethane. The combined organic layers are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue is purified by flash chromatography on silica gel to afford the titled compound.

Illustrative synthesis of compound 239: 1-[3-(azetidin-1-yl)phenyl]-4-{6-[(2-methoxyethyl)(methyl)amino]pyridin-3-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

To a degassed solution of A105 (38 mg, 0.7 mmol, 1.0 equiv) and azetidine (7 μL, 0.10 mmol, 1.5 equiv) in anhydrous THF (0.3 mL) at RT under nitrogen atmosphere in a sealed vial was added XPhos Pd G1 (CAS 1028206-56-5, 5 mg, 0.007 mmol, 0.1 equiv) followed by 1 N LiHMDS in THF (315 μL, 0.315 mmol, 4.5 equiv). The reaction mixture was purged with nitrogen and stirred at RT overnight. Additional azetidine (3.5 μL, 0.05 mmol, 0.5 equiv) and XPhos Pd G1 (CAS 1028206-56-5, 5 mg, 0.007 mmol, 0.1 equiv) were added at RT. The reaction mixture was purged again with nitrogen and stirred for 2 h. Then the reaction mixture was cooled down and volatiles were removed in vacuo. The resulting residue was taken up in dichloromethane and water and acidified with acetic acid. The two phases were separated, and the aqueous phase was extracted with dichloromethane. The combined organic layers were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The resulting residue was purified by preparative HPLC to deliver the titled compound.

Method J8: Tandem Methylation and Saponification

60% NaH in mineral oil (6.0 equiv) is added to a solution of an ester/alcohol or a 2-oxo-1,2-dihydropyridin-4-yl/ester (1 equiv) in THF. The reaction mixture is stirred at RT for 5 minutes, and a C₁-C₆ alkyl halide (6.0 equiv) was added. The reaction mixture was stirred at RT for 1-24 hours and then concentrated. The residue was purified by silica gel chromatography to give the ether/carboxylic acid or the 1-methyl-2-oxo-1,2-dihydropyridin-4-yl/carboxylic acid.

Illustrative synthesis of compound 431: 1-cyclohexyl-4-[4-(methoxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

60% NaH in mineral oil (24 mg, 0.60 mmol, 6.0 equiv) was added to a solution of E134 (42 mg, 0.10 mmol) in THF (1 mL). The reaction mixture was stirred at RT for 5 minutes, and methyl iodide (0.037 mL, 0.60 mmol, 6.0 equiv) was added. The reaction mixture was stirred at RT for 16 hours and then concentrated. The residue was purified by silica gel chromatography (DCM/MeOH: 100/0 to 90/10) to give the titled compound.

Method J9: Acylation of Amine

A heterocyclic amine at either the R² or R³ positions can be reacted with an acid chloride or chloroformate dissolved is solvents such as dichloromethane, tetrahydrofuran or DMF at 0° C. to ambient temperature over 0.5-4 hours in the presence a tertiary amine base or an inorganic carbonate base. The reaction mixture is extractively worked up and/or purified chromatographically either by flash chromatography or by preparative HPLC.

Illustrative synthesis of compound 166: 1-cyclohexyl-4-[2-(dimethylamino)pyrimidin-5-yl]-3-[1-(methoxycarbonyl)azetidin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Diisopropylethylamine (0.55 mL, 3.12 mmol, 6.0 equiv) and DMAP (13 mg, 0.104 mmol, 0.2 equiv) were added to a solution of AI21 (220 mg, 0.52 mmol, 1 equiv) in dichloromethane (2 mL). The mixture was cooled to 0° C. and methyl chloroformate (CAS: 79-22-1, 81 μL, 0.104 mmol, 2.0 equiv) was added. The reaction mixture was warmed up to RT and stirred for 1.5 h. The reaction mixture was partitioned between dichloromethane and water. The two phases were separated, and the aqueous phase was extracted with dichloromethane. The combined organic phase were dried over MgSO₄, filtered and concentrated in vacuo. The residue was purified by preparative HPLC to afford the titled compound.

Synthesis of compounds 587 and 588: 4-[(3aR,7aS)-1-acetyloctahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid and 4-[(3aS,7aR)-1-acetyloctahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Step 1: sodium rac-3-cyclobutyl-4-[(3aR,7aS)-octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

rac-4-[(3aR,7aS)-1-(tert-Butoxycarbonyl)octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid (Compound 549, 1.00 g, <1.9 mmol) was dissolved into anhydrous CH₂Cl₂ (8.0 mL), treated with TFA (2.0 mL), stirred at room temperature for two hours and then concentrated. The residue was redissolved into CH₂Cl₂, treated with aqueous K₂HPO₄ and basified to pH 11+ with aqueous NaOH. Brine was added, and the mixture was extracted with 10% MeOH/CH₂Cl₂. The separated organic phase was dried (Na₂SO₄), passed through a short column of Na₂SO₄ and concentrated to give the titled compound (452 mg).

¹H NMR (500 MHz, methanol-d₄) δ ppm 1.69-1.77 (m, 1H), 1.98-2.21 (m, 5H), 2.40-2.66 (m, 6H), 2.94-3.01 (m, 2H), 3.15-3.3 (m, 3H), 3.32-3.36 (m, 1H), 4.07-4.15 (m, 1H), 7.24-7.28 (m, 1H), 7.38 (s, 1H), 7.47-7.51 (m, 2H), 8.35-8.38 (m, 2H); MS (ESI) m/z 418 (M+H)⁺.

Step 2: 4-[(3aR,7aS)-1-acetyloctahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid and 4-[(3aS,7aR)-1-acetyloctahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Sodium rac-3-cyclobutyl-4-[(3aR,7aS)-octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (209 mg, 0.50 mmol) and N-methylmorpholine (220 μL, 2.0 mmol) were suspended in DMF (2.5 mL) and chilled with a water ice bath. A solution of acetyl chloride (50 μL, 0.70 mmol) in dichloromethane (500 μL) was added dropwise, and the mixture was stirred for two minutes before the bath was removed. The cloudy solution was stirred another thirty minutes at room temperature before being diluted with EtOAc and placed directly on silica for chromatography (EtOAc, then 0 to 20% MeOH/MeCN, then 0.1% TFA/19.9% MeOH/80% MeCN) to give rac-4-[(3aR,7aS)-1-acetyloctahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid (236 mg).

The racemate was then subjected to preparative supercritical fluid chromatography set to maintain a maximum back pressure of 100 MPa using a Chiralcel® OJ-H (21×250 mm) column with the sample at a concentration of 10 mg/mL in methanol using 35% methanol in CO₂ at a flow rate of 45 mL/minute to provide both enantiomers separately. The first enantiomer eluted (retention time=5.4 minutes, compound 588), and the second enantiomer eluted (retention time=7.4 minutes, compound 587) as the titled compounds (stereochemistry arbitrarily assigned).

Synthesis of compound 610: rac-3-cyclobutyl-1-phenyl-4-[(3aR,7aS)-1-{[(propan-2-yl)oxy]carbonyl}octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Sodium rac-3-cyclobutyl-4-[(3aR,7aS)-octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (˜0.1 mmol, Step 1 in the preparation of compounds 587 and 588) was dissolved into THF (1.0 mL), treated with 1 M aqueous Na₂CO₃ (150 μL, 0.15 mmol) followed by 1 M isopropyl chloroformate in toluene (300 μL, 0.3 mmol) and stirred about 12 minutes before being quenched with 3 M aqueous NaOH (50 μL) and diisopropylamine (50 μL). The mixture was stirred thoroughly and then acidified with TFA (10 drops). Sodium chloride was added, and the wet salts were separated and extracted with EtOAc. The combined organic phases were concentrated and chromatographed quickly on silica (EtOAc/CH₂Cl₂). Fractions containing product were concentrated and purified by preparative HPLC on a Waters® Sunfire™ C8 column (30×150 mm) with a 60 to 100% gradient of acetonitrile in 0.1% aqueous TFA at 50 mL/min to give the titled compound (10 mg).

Method J10: Nucleophilic Substitution on the Central Core with Amines

A mixture of the chloride or triflate intermediate HP (1.0 equiv), the amine as free base or hydrochloride salt (from 1 to 10 equiv) and DIPEA (from 1 to 15 equiv) in acetonitrile, N,N-dimethylacetamide or a mixture of anhydrous acetonitrile and DMSO in a sealed tube or a round bottom flask is heated at a temperature ranging from 50 to 150° C. for 1 h to several days (up to 8 days). The reaction mixture is cooled to RT. The resulting residue is either purified by precipitation or by flash chromatography on silica gel or preparative HPLC to afford the titled compound or alternatively partitioned between either dichloromethane or ethyl acetate and water. The two phases are then separated, and the aqueous phase is extracted with either ethyl acetate or dichloromethane. The combined organic phases are dried, filtered and concentrated in vacuo, and the resulting crude mixture is either used as such or purified by flash chromatography on silica gel to afford the titled compound.

Alternatively, a mixture of the chloride or triflate intermediate HP (1.0 equiv), the amine as free base or hydrochloride salt (from 1 to 10 equiv) and triethylamine (from 1 to 15 equiv) in N,N-dimethylacetamide is heated with microwave irradiation at a temperature ranging from 130 to 150° C. for 5 to 20 min. DBU (1 to 2 equiv) was added, and the reaction mixture is again heated with microwave irradiation for 1 to 4 hours at 130 to 150° C. Upon cooling, solids are collected and then precipitated from a solvent such as acetonitrile or purified by preparative HPLC.

Illustrative synthesis of compound 576: 4-([1,4′-bipiperidin]-1′-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

A suspension of intermediate HP10 (328 mg, 1.0 mmol), 1,4′-bipiperidine (253 mg, 1.50 mmol) and triethylamine (350 μL, 2.5 mmol) in anhydrous DMA (800 μL) was heated in a Biotage® Initiator microwave synthesizer at 150° C. for fifteen minutes. DBU (180 μL, 1.2 mmol) was added, and the reaction mixture was heated with microwave irradiation at 150° C. for one hour and 45 minutes, brought to room temperature, diluted with water (8 mL) and washed with 1:2 EtOAc/MTBE. The aqueous phase was acidified with 3 M aqueous citric acid (400 μL) to precipitate the product, which was collected by filtration, washed with water and dried under vacuum to give the titled compound (423 mg).

Illustrative synthesis of compound 560: 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

A suspension of intermediate HP10 (230 mg, 0.70 mmol), 4-(piperidin-4-yl)morpholine (177 mg, 1.05 mmol) and triethylamine (245 μL, 1.76 mmol) in anhydrous DMA (600 μL) was heated in a Biotage® Initiator microwave synthesizer at 140° C. for five minutes. DBU (105 μL, 0.70 mmol) was added, and the reaction mixture was heated with microwave irradiation at 140° C. for three hours, brought to room temperature and filtered through a C18 column (MeOH/H2O). The filtrate was concentrated, and the residual solids were washed with EtOAc, boiled in MeCN and allowed to cool to room temperature. The solid was collected by filtration, rinsed with acetonitrile and dried under vacuum to give the titled compound (305 mg).

Illustrative synthesis of compound 575: 3-cyclobutyl-4-{4-[2-(morpholin-4-yl)ethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

A suspension of intermediate HP10 (164 mg, 0.50 mmol), 4-(2-(piperidin-4-yl)ethyl)morpholine (149 mg, 0.75 mmol) and triethylamine (175 μL, 1.26 mmol) in anhydrous DMA (400 μL) was heated in a Biotage® Initiator microwave synthesizer at 150° C. for fifteen minutes. DBU (90 μL, 0.60 mmol) was added, and the reaction mixture was heated by microwave irradiation at 150° C. for one hour, brought to room temperature, diluted with water (8 mL) and concentrated. The residue was slurried in acetonitrile and the solids were collected by filtration to give the titled compound (155 mg).

Illustrative synthesis of compound 544: 3-cyclobutyl-4-[(3R)-3-(hydroxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

A suspension of 4-chloro-3-cyclobutyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylic acid (HP10, 164 mg, 0.50 mmol), (R)-piperidin-3-ylmethanol (86 mg, 0.75 mmol) and triethylamine (175 μL, 1.26 mmol) in anhydrous DMA (400 μL) was heated in a microwave reactor at 150° C. for fifteen minutes. DBU (90 μL, 0.60 mmol) was added, and the reaction mixture was heated in the reactor at 150° C. for one hour, brought to room temperature, diluted with water (8 mL), concentrated, and purified by preparative HPLC on a Waters® T3 column (30 mm×100 mm) with a 20 to 100% gradient of acetonitrile in 10 mM aqueous ammonium acetate to give the titled compound (156 mg).

Illustrative synthesis of compound 549: rac-4-[(3aR,7aS)-1-(tert-butoxycarbonyl)octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Intermediate HP10 (164 mg, 0.50 mmol), the tert-butyl rac-(3aR,7aS)-octahydro-1H-pyrrolo[3,2-c]pyridine-1-carboxylate (181 mg, 0.80 mmol, CAS#848410-13-9) and diisopropylethylamine (175 μL, 1.0 mmol) were heated in DMSO (350 μL) at 120° C. for a day, brought to room temperature, and partitioned between EtOAc and 2:1 water/brine (600 μL). The aqueous phase was separated and extracted thrice with EtOAc, and the combined organic phases were acidified with TFA, concentrated and chromatographed on silica (0.1% TFA in 1:1 EtOAc/heptane) to give the titled compound (274 mg).

Synthesis of compound 288: 3-methyl-4-(4-methyl-3-oxo-1-oxa-4,9-diazaspiro[5.5]undecan-9-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

To a 4 mL vial equipped with a stir bar was added 4-chloro-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid (40 mg, 0.14 mmol, HP17 dissolved in 400 μL of acetonitrile. To this solution, was then added 4-methyl-1-oxa-4,9-diazaspiro[5.5]undecan-3-one (153 mg, 5 eq, 0.7 mmol) followed by diisopropylethylamine (145 μL, 6 equiv, 0.83 mmol), and the mixture was heated at 100° C. with stirring for 16 hours. After completion of the reaction, the mixture was concentrated. The residue was dissolved in DMSO and purified by reverse phase HPLC (C18, 0-100% CH₃CN/water (0.1% TFA)). A gradient of acetonitrile (A) and 0.1% trifluoroacetic acid in water (B) was used, at a flow rate of 50 mL/min (0-0.5 min 10% A, 0.5-6.0 min linear gradient 10-100% A, 6.0-7.0 min 100% A, 7.0-8.0 min linear gradient 100-10% A). to afford the title compound.

Illustrative synthesis of compound 571: 3-cyclobutyl-4-[4-(2-methoxyethyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

A suspension of intermediate HP10 (164 mg, 0.50 mmol), 1-(2-methoxyethyl)piperazine (108 mg, 0.75 mmol) and triethylamine (175 μL, 1.26 mmol) in anhydrous DMA (400 μL) was heated in a Biotage® Initiator microwave synthesizer at 150° C. for fifteen minutes. DBU (90 μL, 0.60 mmol) was added, and the reaction mixture was heated by microwave irradiation at 150° C. for one hour, brought to room temperature, diluted with water (8 mL) and concentrated. The residue was chromatographed on a C18 column (0 to 50% MeOH/H₂O), and the impure product was purified by preparative HPLC on a Waters® Sunfire™ C8 column (30×150 mm) with a 30 to 60% gradient of acetonitrile in 10 mM aqueous ammonium acetate at 50 mL/min to give the titled compound (147 mg).

Illustrative synthesis of compound 590: 3-cyclobutyl-4-{[(oxan-4-yl)methyl]amino}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Intermediate HP10 (82 mg, 0.25 mmol), 4-aminomethyltetrahydropyran (40 mg, 0.35 mmol), DBU (67 μL, 0.45 mmol) and TMEDA (53 μL, 0.35 mmol) were placed into anhydrous DMA (170 μL) and heated in a Biotage® Initiator microwave synthesizer at 150° C. for one hour. More DBU (11 μL, 0.07 mmol) was added, and the reaction mixture was heated another hour at 160° C. before being brought to room temperature. The reaction mixture was diluted with dichloromethane and washed with water, which was separated and back-extracted with more CH₂Cl₂. The organic phases were washed with brine, which was separated and back-extracted with CHCl₃. The combined organic phases were dried (Na₂SO₄), concentrated and purified by preparative HPLC on a Waters® Sunfire™ C8 column (30×150 mm) with a 45 to 75% gradient of acetonitrile in 0.1% aqueous TFA at 50 mL/min to give the titled compound (26 mg).

Illustrative synthesis of compound 655: 3-cyclobutyl-4-({[(2S)-oxolan-2-yl]methyl}amino)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

A mixture of intermediate HP10 (82 mg, 0.25 mmol), (S)-(tetrahydrofuran-2-yl)methanamine (40 mg, 0.40 mmol) and triethylamine (88 μL, 0.63 mmol) in anhydrous DMA (200 μL) was heated in a Biotage® Initiator microwave synthesizer at 120° C. for ten minutes. DBU (38 μL, 0.25 mmol) was added, and the reaction mixture was heated at 150° C. for three hours, then brought to room temperature, loaded on silica with EtOAc and eluted (0 to 10% MeOH/MeCN then 0.4% TFA/19.6% MeOH/80% MeCN). The impure product was then purified by preparative HPLC on a Waters® Sunfire™ C8 column (30×150 mm) with a 45 to 75% gradient of acetonitrile in 0.1% aqueous TFA at 50 mL/min to give the titled compound (41 mg).

Illustrative synthesis of compound 671: 4-[(3S)-3-{[(tert-butoxycarbonyl)amino]methyl}pyrrolidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

A suspension of intermediate HP02 (230 mg, 0.70 mmol), (R)-tert-butyl(pyrrolidin-3-ylmethyl)carbamate (˜200 mg, 1.0 mmol) and triethylamine (245 μL, 1.76 mmol) in anhydrous DMA (600 μL) was heated in a Biotage® Initiator microwave synthesizer at 150° C. for fifteen minutes. DBU (125 μL, 0.84 mmol) was added, and the reaction mixture was heated at 150° C. with microwave irradiation for one hour, brought to room temperature, treated with acetic acid (200 μL) and chromatographed on silica (100% MeCN then 0.2% HOAc in 1:9 MeOH/MeCN). The appropriate fractions were concentrated, and the residue was swirled with water/methanol until a precipitate formed. The solid was collected by filtration, rinsed with methanol/water and dried under vacuum to give the titled compound (291 mg).

Illustrative synthesis of compound 672: 4-[(3R)-3-{[(tert-butoxycarbonyl)amino]methyl}pyrrolidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

A suspension of intermediate HP02 (230 mg, 0.70 mmol), (S)-tert-butyl(pyrrolidin-3-ylmethyl)carbamate (˜200 mg, 1.0 mmol) and triethylamine (245 μL, 1.76 mmol) in anhydrous DMA (600 μL) was heated in a Biotage® Initiator microwave synthesizer at 150° C. for fifteen minutes. DBU (125 μL, 0.84 mmol) was added, and the reaction mixture was heated at 150° C. with microwave irradiation for one hour, brought to room temperature, treated with acetic acid (200 μL) and chromatographed on silica (100% MeCN then 0.2% HOAc in 1:9 MeOH/MeCN). The appropriate fractions were concentrated, and the residue was swirled with water/methanol until a precipitate formed. The solid was collected by filtration, rinsed with methanol/water and dried under vacuum to give the titled compound (292 mg).

Illustrative synthesis of compound 763: 1-(4-fluorophenyl)-5-methyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

A suspension of HP27 (70 mg, <0.20 mmol), 4-morpholinopiperidine (51 mg, 0.30 mmol) and triethylamine (70 μL, 0.50 mmol) in anhydrous DMA (170 μL) was heated in a microwave reactor at 150° C. for fifteen minutes. DBU (30 μL, 0.20 mmol) was added, and the reaction mixture was heated at 180° C. for an hour and then at 200° C. for 2.5 hours. The reaction mixture was brought to room temperature and purified by preparative HPLC on a Waters® Sunfire™ C8 column (30×150 mm) with a 25 to 35% gradient of acetonitrile in 10 mM aqueous ammonium acetate to give the titled compound.

Illustrative synthesis of compound 811: 1-(4-fluorophenyl)-3-(propan-2-yl)-4-{4-[(pyrrolidin-1-yl)methyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

A suspension of the chloropyrazolopyridine, HP11 (267 mg, 0.80 mmol), 4-(pyrrolidin-1-ylmethyl)piperidine (202 mg, 1.20 mmol) and triethylamine (280 μL, 2.0 mmol) in anhydrous DMA (700 μL) was heated in a microwave reactor at 150° C. for fifteen minutes. DBU (145 μL, 0.96 mmol) was added and the reaction mixture was heated at 150° C. for 1 hour and 45 minutes, brought to room temperature, diluted with water (7 mL) and washed with 1:2 EtOAc/MTBE. The aqueous phase was acidified with 3 M aqueous citric acid (400 μL) and cooled with a water ice bath to initiate precipitation. The mixture was stirred at room temperature, and when most of the initial gum had solidified, then the suspension was cooled with a water ice bath. The solids were collected by filtration, rinsed with water and chromatographed on silica (20% MeOH/CH₃CN then 1% concentrated aqueous NH₄OH/9% H₂O/CH₃CN) to give the titled compound.

Illustrative synthesis of compound AI27: 3-cyclobutyl-4-[4-(hydroxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

To a solution of HP10 (0.502 g, 1.532 mmol) and 4-piperidinemethanol (0.441 g, 3.83 mmol) in N,N-dimethylacetamide (DMA, 1.5 mL) was added diisopropylethylamine (1.5 mL, 8.59 mmol), and the reaction mixture was then stirred at 150° C. for 12 hours. The reaction mixture was then partitioned between dichloromethane and 1 N HCl. The organic fraction was separated, dried over anhydrous sodium sulfate, filtered, and concentrated under vacuum. The residue was purified on silica gel, eluting with a gradient of 0-5% MeOH/DCM to give the titled compound. ¹H NMR (400 MHz, DMSO-d₆) δ ppm 1.41 (qd, J=12.2, 3.7 Hz, 2H), 1.60 (dtdd, J=13.2, 10.0, 6.2, 3.6 Hz, 1H), 1.83 (dd, J=13.3, 3.4 Hz, 2H), 1.87-2.12 (m, 3H), 2.36 (dtd, J=11.8, 8.5, 3.1 Hz, 2H), 2.51 (dd, J=9.3, 2.3 Hz, 1H), 2.76-2.96 (m, 2H), 3.54 (dd, J=9.4, 6.2 Hz, 2H), 3.94 (p, J=8.4 Hz, 1H), 4.55 (s, 1H), 7.24-7.33 (m, 2H), 7.47-7.58 (m, 2H), 8.30 (d, J=8.0 Hz, 2H).

Method J11: Reductive Amination

To a solution of amine (1 equiv) in anhydrous methanol at RT is added paraformaldehyde (CAS: 30525-89-4, 5.0 equiv). A drop of acetic acid is added, and the reaction mixture is stirred for 1 h at RT. Sodium cyanoborohydride (CAS: 25895-60-7, 7 mg, 0.1 mmol, 5 equiv) is then introduced and the reaction mixture is stirred at RT until completion. The reaction mixture is then partitioned between DCM and water. The two phases are separated, and the aqueous phase is extracted with dichloromethane. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo to afford the alkylated amine compound which is used as such or purified by flash chromatography on silica gel or preparative HPLC.

Illustrative synthesis of compound 87: 3-[(dimethylamino)methyl]-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

To a solution of A102 (9 mg, 0.02 mmol, 1 equiv) in anhydrous methanol at RT was added paraformaldehyde (CAS: 30525-89-4, 4 mg, 0.1 mmol, 5.0 equiv). A drop of acetic acid was added, and the reaction mixture was stirred for 1 h at RT. Sodium cyanoborohydride (CAS: 25895-60-7, 7 mg, 0.1 mmol, 5 equiv) was then introduced. The reaction mixture was stirred at RT overnight. The reaction mixture was then partitioned between DCM and water. The two phases were separated, and the aqueous phase was extracted with dichloromethane. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The residue was purified by preparative HPLC to afford the titled compound.

Method J12: Tandem Nucleophilic Substitution on the Central Core and Hydrolysis

To a solution of intermediate halogenated pyrazolopyridine (1.0 equiv) in anhydrous DMSO is added morpholine (2.0 equiv), and the reaction mixture is stirred at 100° C. until completion. The reaction mixture is added to water and extracted with ethyl acetate. The organic layer is washed with brine, dried over MgSO₄, filtered and concentrated. The crude is used directly in the next step without further purification.

The crude residue is suspended in a 6 N HCl aqueous solution, and the resulting mixture is heated to reflux overnight. The mixture is cooled to room temperature, quenched by addition of a saturated NaHCO₃ solution and extracted with EtOAc. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The crude residue is purified by silica gel chromatography or by preparative HPLC.

Illustrative synthesis of compound 118: 3-methyl-4-(morpholin-4-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Step 1: 3-methyl-4-morpholino-1-phenyl-pyrazolo[3,4-b]pyridine-6-carbonitrile

To a solution of HP18 (21 mg, 0.08 mmol, 1.0 equiv) in anhydrous DMSO (0.5 mL) was added morpholine (14 μL, 0.16 mmol, 2.0 equiv), and the reaction mixture was stirred at 100° C. for 1 h. The reaction mixture was added to water and extracted with ethyl acetate. The organic layer was washed with brine, dried over MgSO₄, filtered and concentrated. The crude residue was used directly in the next step without further purification.

Step 2: 3-methyl-4-(morpholin-4-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

The crude residue was suspended in a 6 N HCl aqueous solution, and the resulting mixture was heated to reflux overnight. The mixture was cooled to room temperature, quenched by addition of a saturated NaHCO₃ solution and extracted with EtOAc. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The crude residue was purified by silica gel chromatography (DCM/MeOH: 100/0 to 95/5) to deliver the titled compound.

Method J13: Alkylation of Alcohols and Carbamates

To a solution of the corresponding alcohol or carbamate (1.0 equiv) in anhydrous DMF under a nitrogen atmosphere at 0° C. is added sodium hydride or KHMDS (1-3 equiv). The resulting solution is stirred at 0° C. for 30 min, and then methyl iodide (1-4 equiv) is added. The reaction mixture is stirred at 0° C. to room temperature until completion. The mixture is then quenched by addition of a saturated NH₄Cl solution and filtered. The filtrate is concentrated in vacuo. The residue is dissolved in water, and the pH is adjusted to 4-5 with acetic acid. The resulting mixture is stirred at RT for 1 h. If a filterable suspension is obtained, the suspension formed is collected by filtration, washed with water and dried in vacuo. The crude solid is then purified by silica gel flash chromatography or preparative HPLC. In other cases, the mixture is extracted with EtOAc. The combined organic phases are washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The crude residue is purified by silica gel chromatography or by preparative HPLC.

Illustrative synthesis of compound 143: 4-(4-methoxypiperidin-1-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

To a solution of ethyl 4-(4-hydroxy-1-piperidyl)-3-methyl-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate E238 (218 mg, 0.57 mmol, 1.0 equiv) in anhydrous DMF (4.4 mL) under a nitrogen atmosphere was added sodium hydride (60% in oil, 30 mg, 0.74 mmol, 1.3 equiv). The resulting solution was stirred at 0° C. for 30 min, and then methyl iodide (47 μL, 0.31 mmol, 1.3 equiv) was added. The reaction mixture was stirred at 0° C. for 1 h. Then sodium hydride (60 mg, 1.48 mmol, 2.6 equiv) and methyl iodide (181 μL, 2.96 mmol, 5.0 equiv) were added, and the reaction mixture was stirred at 0° C. for 2 h. The mixture was quenched by addition of a saturated NH₄Cl solution and filtered. The filtrate was concentrated in vacuo. The residue was dissolved in water, and the pH was adjusted to 4-5 with acetic acid. The resulting mixture was stirred at room temperature for 1 h. The suspension that formed was filtered, and the solids were washed with water and dried in vacuo. The crude solid was then purified by silica gel flash chromatography (heptane/EtOAc/AcOH: 100/0/0.5 to 30/70/0.5) to afford the titled compound.

Synthesis of compound 674: 4-[(3R)-3-{[(tert-butoxycarbonyl)(methyl)amino]methyl}pyrrolidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

4-[(3S)-3-{[(tert-Butoxycarbonyl)amino]methyl}pyrrolidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid (compound 671, 148 mg, 0.30 mmol) was placed under nitrogen, dissolved into anhydrous DMF (3.0 mL) and cooled with a water ice bath. 1 M KHMDS in THF (900 μL, 0.90 mmol) was added dropwise over a few minutes, and after a few more minutes, iodomethane (75 μL, 1.2 mmol) which had previously been passed through basic alumina was added dropwise over several minutes too. A few minutes later the reaction vial was removed from the bath and the contents were stirred at room temperature for two hours before being treated with 3 M aqueous NaOH (300 μL). After 45 minutes, the reaction mixture was filtered through silica (0 then 0.5% HOAc/EtOAc) and concentrated. The concentrate was diluted with water and extracted thrice with MTBE. The combined organic phases were washed with water then brine, dried (Na₂SO₄) and concentrated to give the titled compound (141 mg).

Synthesis of compound 675: 4-[(3S)-3-{[(tert-butoxycarbonyl)(methyl)amino]methyl}pyrrolidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

4-[(3R)-3-{[(tert-Butoxycarbonyl)amino]methyl}pyrrolidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid (compound 672, 148 mg, 0.30 mmol) was placed under nitrogen, dissolved into anhydrous DMF (3.0 mL) and cooled with a water ice bath. 1 M KHMDS in THF (900 μL, 0.90 mmol) was added dropwise over a few minutes, and after a few more minutes, iodomethane (75 μL, 1.2 mmol) which had previously been passed through basic alumina was added dropwise over several minutes too. A few minutes later the reaction vial was removed from the bath and the contents were stirred at room temperature for two hours before being treated with 3 M aqueous NaOH (300 μL). After 45 minutes the reaction mixture was filtered through silica (0 then 0.5% HOAc/EtOAc) and concentrated. The concentrate was diluted with water and extracted thrice with MTBE. The combined organic phases were washed with water then brine, dried (Na₂SO₄) and concentrated to give the titled compound (154 mg).

Method J14: Debenzylation by Hydrogenolysis

A suspension of the corresponding benzyl ether (1.0 equiv) and Pd/C (10%) in THF/MeOH is hydrogenated until completion. The reaction mixture is filtered over Celpure® and washed with DCM and MeOH, and the filtrate is concentrated in vacuo. The crude residue is then purified by silica gel chromatography or preparative HPLC.

Illustrative synthesis of compound 198: 4-[4-(3-hydroxypiperidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

A suspension of AI03 (29 mg, 0.56 mmol, 1.0 equiv) and Pd/C (10%, 20 mg) in THF/MeOH (2 mL/2 mL) was hydrogenated overnight. The reaction mixture was filtered over Celpure® and washed with DCM and MeOH, and the filtrate was concentrated in vacuo. The crude was purified by silica gel chromatography (DCM/MeOH: 100/0 to 90/10) to give the titled compound.

Method J15: Deprotection of Amine by Hydrolysis

To a solution of the corresponding acid (1.0 equiv) in DCM is added trifluoroacetic acid (10% by volume). The reaction mixture is stirred at RT until completion and then concentrated in vacuo. The residue is purified by silica gel chromatography or preparative HPLC to deliver the titled compound.

Illustrative synthesis of compound 550: 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-phenyl-3-[(pyrrolidin-3-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

To a solution of compound 552 (30 mg, 0.049 mmol, 1.0 equiv) in DCM (1 mL) was added trifluoroacetic acid (0.1 mL, 10% by volume). The reaction mixture was stirred at RT until completion, and then concentrated in vacuo. The residue was purified by preparative HPLC to deliver the titled compound.

Synthesis of compound 676: 3-cyclobutyl-4-{(3S)-3-[(methylamino)methyl]pyrrolidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

4-[(3R)-3-{[(tert-Butoxycarbonyl)(methyl)amino]methyl}pyrrolidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid (Compound 674, 17 mg, 34 μmol) was dissolved into anhydrous dichloromethane (0.8 mL), treated with TFA (0.2 mL) stirred at room temperature for about 100 minutes, and then concentrated under vacuum. The residue was passed through a C18 column (1 g Burdick and Jackson® column, 13 mm diameter) eluted with 30 to 60% MeOH/H₂O to give the titled compound (15 mg).

Method J16: Tandem Nucleophilic Substitution/Saponification

-   R^(m): isopropyl, ethyl

The intermediate ester (1 equiv.) is suspended in a mixture of appropriate alcohol for the nucleophilic substitution and THF. 1 N NaOH (from 17 to 19 equiv) is added, and the reaction mixture is stirred at RT or 50° C. until full conversion is observed. 1 N HCl (2 equiv) and a phosphate buffer solution (pH 6.2) are added. The mixture is concentrated under reduced pressure, and the crude residue is partitioned between water and dichloromethane. The organic phase is dried over sodium sulfate, filtered and concentrated under reduced pressure to give the titled compound.

Illustrative synthesis of compound AI29: 3-cyclobutyl-1-(2-ethoxypyrimidin-4-yl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

The intermediate ester E422 (30 mg, 57 μmol) was suspended in a mixture of ethanol (8 mL) and THF (3 mL). 1 N NaOH (1 mL, 1 mmol) was added, and the reaction mixture was stirred at RT for 2 hours. 1N HCl (1 mL, 1 mmol) and a phosphate buffer solution (pH 6.2, 5 mL) were added. The mixture was concentrated under reduced pressure, and the crude residue was partitioned between water and dichloromethane. The organic phase was dried over sodium sulfate, filtered and concentrated under reduced pressure to give the titled compound.

Method J17: S_(N)Ar on Fluoropyridine

The (6-fluoro-pyridin-3-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid (1 eq) is heated together with the amine (1.05 eq) and DIPEA (1.25 eq) in NMP at 100° C. for 18 hours. Mixture is diluted with EtOAc and water. Isolation of the organic layer and subsequent concentration yields the desired product.

Illustrative synthesis of compound 868: 3-Cyclobutyl-1-cyclohexyl-4-[6-(4-cyclopropylpiperazin-1-yl)-pyridin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

3-Cyclobutyl-1-cyclohexyl-4-(6-fluoro-pyridin-3-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid (200 mg, 0.51 mmol) was heated together with 1-cyclopropylpiperazine ([20327-23-5], 64 μL, 0.53 mmol) and DIPEA (110 μL, 0.64 mmol) in NMP (2 mL) at 100° C. for 18 hours. Mixture was diluted with EtOAc and water. Isolation of the organic layer and subsequent concentration yielded the titled compound.

Method J18: Suzuki with Alkyl-BF₃ Salts

-   -   LG³ is a leaving group suitable for the coupling reaction     -   G^(x) is -G^(3A) or -G^(3B)-L¹-G^(3C)

The aryl halide (1 eq) is mixed together with the alkyl-BF₃ salt (1.5 eq), Pd(dppf)Cl₂.DCM (CAS 95464-05-4, 0.05 eq) and CS₂CO₃ (3 eq) in a mixture of THF/H₂O (10/1). The mixture is put under N₂ atmosphere and heated at 80° C. overnight.

If the method is performed on an ester, the ester can be subsequently hydrolyzed to the acid by the addition of LiOH (2 eq) and heating at 50° C. The titled compound is isolated by acidifying with citric acid till pH=6 and extraction with EtOAc. Concentration, possibly followed by chromatographic purification, gives the titled compound.

Illustrative synthesis of compound 893: 3-Cyclobutyl-1-(4-fluoro-phenyl)-4-(4-morpholin-4-yl-piperidin-1-ylmethyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

HP19 (352 mg, 0.98 mmol) was mixed together with potassium trifluorido{[4-(morpholin-4-yl)piperidin-1-yl]methyl}borate (426 mg, 1.47 mmol), Pd(dppf)Cl₂.DCM (CAS 95464-05-4, 40 mg, 0.05 mmol) and Cs₂CO₃ (959 mg, 2.94 mmol) in a mixture of THF/H₂O (10/1, 5 mL). The mixture was put under a N₂ atmosphere and heated at 80° C. overnight.

Next, LiOH (82 mg, 2 mmol) was added, and the mixture was heated at 50° C. The titled compound was isolated by acidifying with citric acid till pH=6 and extraction with EtOAc. Concentration, followed by automated preparative chromatographic purification, gave the titled compound.

Method J19: Suzuki and Subsequent Hydrolysis

The aryl chloride (1 eq) is mixed with the boronic ester (or acid) (1.5 eq), Pd(dppf)Cl₂.DCM (CAS 95464-05-4, 0.1 eq) and DIPEA (3 eq) in a mixture of water/dioxane (1/2). The resulting mixture is stirred at 120° C. for 18 hours. Next, LiOH (2 eq) is added, and the mixture is heated at 40° C. After acidifying with 2 M HCl solution, extraction with EtOAc gives an organic phase that is concentrated to give the titled compound.

Method J20: Oxidation of Primary Alcohols to Aldehydes

The primary alcohol is combined with dimethyl sulfoxide and treated with triethylamine (1.5-5 equiv) and pyridine sulfur trioxide complex (1.5-5 equiv) with stirring at ambient temperature. The reaction mixture is stirred for 30 minutes to 2 hours. Additional triethylamine and pyridine sulfur trioxide complex are added as needed to give complete conversion. The reaction mixture is partitioned between dichloromethane and aqueous 1 N HCl. The organic fraction is dried (Na₂SO₄), filtered and concentrated. The residue is purified by silica gel column chromatography.

Illustrative synthesis of AI28: 3-cyclobutyl-4-(4-formylpiperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

To a solution of AI27 (1.685 g, 4.15 mmol) in DMSO (15 mL) were added triethylamine (1.444 mL, 10.36 mmol) and pyridine sulfur trioxide complex (1.649 g, 10.36 mmol). The reaction mixture was stirred at RT for one hour to give a mixture of the aldehyde and starting alcohol. More triethylamine (0.3 mL, 0.5 equivalents) and pyridine sulfur trioxide complex (0.33 gm, 0.5 eq) were added to the reaction mixture, which was stirred at 25° C. for 30 minutes. More triethylamine (0.15 mL, 0.25 equivalents) and pyridine sulfur trioxide complex (0.165 gm, 0.25 equivalents) were added, and the reaction stirred at 25° C. for one hour. The reaction mixture was then partitioned between dichloromethane and 1 N aqueous HCl. The organic layer was separated, dried over anhydrous sodium sulfate, filtered, and concentrated. The residue was purified on silica gel eluting with a gradient of 0-5% MeOH/dichloromethane to give the titled compound. ¹H NMR (400 MHz, CDCl₃) δ ppm 1.97 (dtd, J=14.1, 10.7, 3.8 Hz, 2H), 2.11 (dddd, J=14.6, 9.5, 8.0, 3.7 Hz, 2H), 2.16-2.31 (m, 2H), 2.45 (dddd, J=9.2, 8.0, 6.6, 4.1 Hz, 1H), 2.62 (dddd, J=18.0, 14.8, 11.2, 6.7 Hz, 3H), 3.10 (td, J=12.7, 11.7, 2.8 Hz, 2H), 3.66 (dt, J=12.4, 4.1 Hz, 2H), 3.98 (p, J=8.4 Hz, 1H), 7.38 (tt, J=7.5, 1.1 Hz, 1H), 7.50 (d, J=0.9 Hz, 1H), 7.52-7.62 (m, 2H), 8.05 (dq, J=7.7, 1.1 Hz, 2H), 9.82 (s, 1H).

Method J21: Reductive Amination of Aldehydes

To a mixture of aldehyde (1 equiv) in dichloroethane is added N,N-diisopropylethylamine (2 equiv). Molecular sieves and amine or amine hydrochloride (1-2 equiv) are added followed by stirring at ambient temperature for 1-5 hours. Sodium triacetoxyborohydride (1-3 equiv) is added followed by stirring for 8 hours to 4 days. The reaction mixture is filtered. The filtrate is concentrated, and the residue can be purified by preparative HPLC.

Alternatively, a mixture of aldehyde (1 equiv), amine or amine hydrochloride (1-2 equiv), acetic acid, and reductant (sodium borohydride, sodium cyanoborohydride, or sodium triacetoxyborohydride; 1-6 equiv; solid or on a solid support, i.e. resin) in dichloroethane, dichloromethane, or a mixture of dichloromethane and methanol is stirred at ambient temperature for 1-24 hours. The reaction mixture is can be purified by preparative HPLC.

Illustrative synthesis of compound 802: 3-cyclobutyl-4-(4-{[(3R)-3-(methoxymethyl)pyrrolidin-1-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

To a suspension of AI28 (0.05 g, 0.124 mmol) in dichloroethane (1 mL) was added N,N-diisopropylethylamine (0.043 mL, 0.247 mmol). Molecular sieves were then added to the reaction mixture followed by addition of (R)-3-(methoxymethyl)pyrrolidine hydrochloride (0.019 g, 0.124 mmol), and the reaction mixture was stirred at 25° C. for three hours. Sodium triacetoxyborohydride (0.039 g, 0.185 mmol) was added to the reaction mixture, which was then stirred at 25° C. for 2 days. The reaction mixture was filtered, and the filtrate was concentrated under vacuum. The residue was then purified by preparative HPLC on a Waters® Sunfire™ C8 column (30×150 mm) with an escalating gradient of acetonitrile in 10 mM aqueous ammonium acetate to give the titled compound.

Method J22: Cross-Coupling to Pyrazole and Ester Hydrolysis

Under an inert atmosphere (glovebox) are combined a palladium catalyst such as tris(dibenzylideneacetone)dipalladium(O) (0.02 to 0.1 equiv), a ligand such as di-tert-butyl(2′,4′,6′-triisopropyl-3,4,5,6-tetramethyl-[1,1′-biphenyl]-2-yl)phosphine (0.05 to 0.3 equiv), and cesium carbonate (1 to 4 equiv) in toluene. The mixture can be heated at 50-100° C. for 20-60 minutes. The pyrazolopyridine (1 equiv) and an aryl halide or heteroaryl halide are added, and the mixture can be heated at 50-100° C. overnight. The reaction mixture is dried, and the intermediate ester can be hydrolyzed with a base such as aqueous 0.5 to 2 N lithium hydroxide, sodium hydroxide or potassium hydroxide at room temperature over 4-24 hours. Upon reaction completion, the coupled/hydrolyzed product can be isolated by preparative chromatography.

Illustrative synthesis of compound 910: 3-cyclobutyl-1-[3-(difluoromethoxy)phenyl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid and intermediate E510: methyl 3-cyclobutyl-1-[3-(difluoromethoxy)phenyl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate

A nitrogen-purged mixture of tris(dibenzylideneacetone)dipalladium(O) (0.0193 g, 0.021 mmol), and di-tert-butyl(2′,4′,6′-triisopropyl-3,4,5,6-tetramethyl-[1,1′-biphenyl]-2-yl)phosphine (0.0251 g, 0.052 mmol) in toluene (2.2 mL) was stirred for 20 minutes and then added to an nitrogen-purged mixture of methyl 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (0.1760 g, 0.441 mmol, E509), 1-bromo-3-(difluoromethoxy)benzene (0.1179 g, 0.529 mmol), and Cs₂CO₃ (0.2143 g, 0.658 mmol). The mixture was heated to 70° C. overnight, diluted with water, extracted with DCM (3×8 mL), dried (Na₂SO₄), and concentrated. The residue was chromatographed on silica (30-60% EtOAc/DCM to 4% MeOH/DCM) and re-chromatographed (2.5-4% iPrOH/DCM) to give methyl 3-cyclobutyl-1-[3-(difluoromethoxy)phenyl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (E510). ¹H NMR (400 MHz, DMSO-d₆) δ ppm 8.28-8.16 (m, 2H), 7.58 (t, J=8.2 Hz, 1H), 7.51-7.03 (m, 3H), 3.95 (dq, J=18.1, 9.8, 8.5 Hz, 1H), 3.88 (s, 3H), 3.63-3.48 (m, 6H), 2.91 (t, J=11.9 Hz, 2H), 2.53-2.48 (m, 4H), 2.46-2.28 (m, 2H), 2.12-1.88 (m, 4H), 1.63 (td, J=13.1, 12.6, 6.4 Hz, 2H); MS (APCI+) m/z 542.4 (M+H)⁺. 1008161A 1 N aqueous solution of sodium hydroxide (0.14 mL, 0.140 mmol) was added to a mixture of methyl 3-cyclobutyl-1-[3-(difluoromethoxy)phenyl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylate (E510, 0.0647 g, 0.119 mmol) in methanol (0.14 mL) and tetrahydrofuran (0.40 mL), The mixture was stirred for 2 hours, diluted with water, and extracted with DCM that was back-extracted with water (2×). The aqueous layer was neutralized with 1 N HCl (0.17 mL), and extracted with DCM, dried (Na₂SO₄), and concentrated to give 3-cyclobutyl-1-[3-(difluoromethoxy)phenyl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid.

Synthesis of acid compound 24: 1-phenyl-3-(propan-2-yl)-4-[4-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Aldehyde (CAS 51980-54-2, 219 mg, 1.25 mmol, 1 equiv), pyruvic acid (81 μL, 1.25 mmol, 1 equiv), and pyrazole AMP04 (251 mg, 1.25 mmol, 1 equiv) were introduced in a sealed tube. Acetic acid (5 mL) was added, and the vial was sealed. The reaction mixture was heated under microwave irradiation at 160° C. for 20 min. Then after cooling down to RT, the vial was opened, and the volatiles were evaporated under reduced pressure. The resulting crude mixture was diluted in methanol and purified by preparative HPLC to afford the titled compound.

Synthesis of acid AI11: 3-(azetidin-3-yloxy)-4-(4-morpholinophenyl)-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Step 1: (1-tert-butoxycarbonylazetidin-3-yl) 3-(1-tert-butoxycarbonylazetidin-3-yl)oxy-4-(4-morpholinophenyl)-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylate

To a solution of acid AI15 (100 mg, 2.4 mmol, 1.0 equiv) in anhydrous NMP (4.4 mL) were added cesium carbonate (235 mg, 0.72 mmol, 3.0 equiv) and 3-iodo-azetidine-1-carboxylic acid tert-butyl ester (210 mg, 0.72 mmol, 3.0 equiv). The resulting solution was stirred at 130° C. under microwave irradiation for 30 min twice. The mixture was then poured into water and extracted with EtOAc. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The crude residue was purified by silica gel chromatography (DCM/MeOH: 100/0 to 95/5) to deliver the bis-alkylated compound.

Step 2: 3-(1-tert-butoxycarbonylazetidin-3-yl)oxy-4-(4-morpholinophenyl)-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylic acid

The previous intermediate (0.033 mmol, 1.0 eq) was dissolved in methanol (2 mL) and 2N NaOH (66 μL, 0.13 mmol, 4.0 eq) in water was added at RT. The solution was stirred for 2 h. The volatiles were evaporated under reduced pressure, and the resulting mixture was diluted with water. The aqueous phase was acidified with aqueous 2 N HCl (70 μL) and extracted with EtOAc. The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The crude residue was directly used in the next step without purification.

Step 3: 3-(azetidin-3-yloxy)-4-(4-morpholinophenyl)-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylic acid

To a solution of the previous acid (1.0 equiv) in DCM (1 mL) was added trifluoroacetic acid (1 mL, 50% volume). The reaction mixture was stirred at RT for 1.5 h and then concentrated in vacuo. The crude residue was directly used in the next step without purification.

Synthesis of AI23: 1-(6-bromopyridin-2-yl)-3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Ester E428 (46 mg, 81 μmol) was dissolved in a mixture of THF/2-propanol (1/2; 9 mL), and 1 N sodium hydroxide (1 mL, 1 mmol) in water was added at RT. The solution was stirred for 2 hours. Aqueous 1 N HCl (1 mL, 1 mmol) was added, and then a phosphate buffer was added (pH 6.2). The solvent was partially removed under reduced pressure, and the resulting mixture was extracted twice with DCM. The combined organic phases were dried over magnesium sulfate, filtered and concentrated under reduced pressure to give the titled compound that was used without further purification.

Synthesis of AI25: 1-(4-fluorophenyl)-4-(4-methoxy[1,4′-bipiperidin]-1′-yl)-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridin-6-yl trifluoromethanesulfonate

A mixture of HP22 (29 mg, 50 μmol), 4-methoxy-1-piperidin-4-ylpiperidine hydrochloride ([930603-98-8], 14 mg, 50 μmol) and DIPEA (35 μL, 200 μmol) in anhydrous DMSO (1 mL) was heated at 100° C. for 2 hours. The reaction mixture was cooled to RT and partitioned between ethyl acetate (50 mL) and water (30 mL). The organic phase was separated, dried over MgSO₄, filtered and concentrated in vacuo. The residue was purified by flash chromatography on silica gel eluting with n-heptane/ethyl acetate and DCM/MeOH to afford the titled compound.

Synthesis of AI26: 1-(4-fluorophenyl)-4-(4-methoxy[1,4′-bipiperidin]-1′-yl)-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carbonitrile

Compound AI25 (16 mg, 26 μmol) was solubilized in dry dimethylformamide (1 mL) in a vial. Zinc cyanide (3.5 mg, 30 μmol) was added, and the reaction mixture was degassed with argon for 5 minutes. Tetrakis(triphenylphosphine)palladium(O) (4 mg, 3 μmol) was added, and the vial was sealed. The reaction mixture was stirred at 120° C. for 2 hours. The reaction mixture was cooled to room temperature, and the mixture was partitioned between a saturated aqueous solution of NaHCO₃ and DCM. The organic phase was dried over sodium sulfate, filtered and concentrated in vacuo. The residue was purified by flash column chromatography eluting with ethyl acetate/DCM/MeOH to give the titled compound.

Synthesis of compound 924: 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-{6-[(propan-2-yl)oxy]pyridin-2-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

Sodium hydride (60% in mineral oil, 100 mg, 2 mmol) was added at 0° C. to 2-propanol (3 mL) under a nitrogen atmosphere. The tube was sealed and then heated at 90° C. for 5 minutes. The reaction mixture was cooled to RT, and a solution of AI23 (30 mg, 55 μmol) in 2-propanol (2 mL) was added dropwise. The reaction mixture was stirred at 90° C. for 1 hour. The reaction mixture was quenched with a saturated aqueous solution of NH₄Cl. A phosphate buffer was added (pH 6.2), and the aqueous phase was extracted twice with DCM/2-propanol (50 mL, 95/5). The combined organic phases were washed with brine, dried over MgSO₄, filtered and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel eluting with DCM/MeOH/1% AcOH to afford the titled compound.

Synthesis of compound 925: 1-(4-fluorophenyl)-3-hydroxy-4-(4-methoxy[1,4′-bipiperidin]-1′-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid

In a sealed tube, compound AI26 (11 mg, 22 μmol) was dissolved in 6 N HCl (3 mL, 18 mmol). The solution was heated at 100° C. for 5 hours and then cooled to RT. The reaction mixture was partitioned between a phosphate buffer solution (pH 6.2) and a mixture of DCM/2-propanol (100 mL, 85/15). The organic phase was dried over sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by flash chromatography eluting with DCM/MeOH/water/AcOH from 90/10/1/1 to 85/15/2/2 to yield the titled compound.

TABLE XIV Table of intermediate acids Int Structure Name SM Method MW Mes AI01

3-(azetidin- 3-yl)-4-(4- morpholino- phenyl)-1- phenyl- pyrazolo[3,4- b]pyridine- 6-carboxylic acid 47 J15 455 456 AI02

3- (methylamino- methyl)-4- (4- morpholino- phenyl)-1- phenyl- pyrazolo[3,4- b]pyridine- 6-carboxylic acid AMP86, ALP01 J2 442 443 AI03

4-[4-(3- benzyloxy- 1- piperidyl) phenyl]-3- methyl-1- phenyl- pyrazolo[3,4- b]pyridine- 6-carboxylic acid E010 J5 518 519 AI04

4-(6-chloro- 3-pyridyl)- 3-methyl-1- phenyl- pyrazolo[3,4- b]pyridine- 6-carboxylic acid 1131- 18-6, ALP07 J2 364 364- 366 AI05

1-(3- bromo- phenyl)-3- isopropyl-4- [6-[2- methoxy- ethyl(methyl) amino]-3- pyridyl] pyrazolo[3,4- b]pyridine- 6-carboxylic acid E346 J1 523 524 AI06

1-(3- bromo- phenyl)-3- isopropyl-4- [4- [methyl(tetra- hydropyran- 4- yl)amino] phenyl] pyrazolo[3,4- b]pyridine- 6-carboxylic acid E347 J1 548 549 AI07

1-(3- benzyloxy- cyclohexyl)-3- isopropyl-4- (4- morpholino- phenyl) pyrazolo[3,4- b]pyridine- 6-carboxylic acid AMP89, ALP01 J2 554 555 AI08

1-(1- benzyloxy- carbonyl-4- piperidyl)-3- isopropyl-4- (4- morpholino- phenyl) pyrazolo[3,4- b]pyridine- 6-carboxylic acid AMP90, ALP01 J2 583 584 AI09

1-(1- benzyloxy- carbonyl- pyrrolidin-3- yl)-3- isopropyl-4- (4- morpholino- phenyl) pyrazolo[3,4- 6]pyridine- 6-carboxylic acid AMP91, ALP01 J2 569 570 AI10

1-(1- benzyloxy- carbonyl-3- piperidyl)-3- isopropyl-4- (4- morpholino- phenyl) pyrazolo[3,4- b]pyridine- 6-carboxylic acid AMP92, ALP01 J2 583 584 AI11

3-(azetidin- 3-yloxy)-4- (4- morpholino- phenyl)-1- phenyl- pyrazolo[3,4- b]pyridine- 6-carboxylic acid AI15 Specific example 471 472 AI12

4-[4-(3- benzyloxy- pyrrolidin-1- yl)phenyl]- 3-methyl-1- phenyl- pyrazolo[3,4- b]pyridine- 6-carboxylic acid E010 J5 504 505 AI13

3- cyclobutyl- 4-[4- (fluoro- methyl)-1- piperidyl]-1- phenyl- pyrazolo[3,4- b]pyridine- 6-carboxylic acid HP10 J4, Specific example 408 409 AI14

4-(6-chloro- 3-pyridyl)- 1- cyclohexyl- 3-isopropyl- pyrazolo[3,4- b]pyridine- 6-carboxylic acid ALP07, AMP23 J2 398- 400 399- 401 AI15

4-(4- morpholino- phenyl)-3- oxo-1- phenyl-2H- pyrazolo[3,4- b]pyridine- 6-carboxylic acid ALP01, 70373- 98-7 J2 416 417 AI16

4-(4- bromo- phenyl)-3- methyl- 1-phenyl- pyrazolo[3,4- b]pyridine- 6-carboxylic acid ALP19, 1131- 18-6 J2 407- 409 408- 410 AI17

1-(3- bromo- phenyl)-3- isopropyl-4- (4- morpholino- phenyl) pyrazolo[3,4- b]pyridine- 6-carboxylic acid ALP01, AMP05 J2 520- 522 521- 523 AI18

4-[6-(4- cyano-1- piperidyl)-3- pyridyl]-3- (3- fluorocyclo- butyl)-1- phenyl- pyrazolo[3,4- b]pyridine- 6-carboxylic acid E120 J1 496 497 AI19

1-[3-(3- benzyloxy- azetidin-1- yl)phenyl]- 3-isopropyl- 4-(4- morpholino- phenyl) pyrazolo[3,4- b]pyridine- 6-carboxylic acid AI17 J7 603 604 AI21

3-(azetidin- 3-yl)-1- cyclohexyl- 4-[2- (dimethyl- amino) pyrimidin-5- yl]pyrazolo [3,4-b] pyridine- 6-carboxylic acid ALP03, AMP38 J2 421 422 AI22

4-[(1-tert- butoxy- carbonyl-4- piperidyl) methoxy]-1- (4- fluorophenyl)- 3-isopropyl- pyrazolo[3,4- b]pyridine- 6-carboxylic acid HP11 J3 512 513 AI23

1-(6- bromo- pyridin- 2-yl)-3- cyclobutyl- 4-[4- (morpholin- 4- yl)piperidin- 1-yl]-1H- pyrazolo[3,4- b]pyridine- 6-carboxylic acid E428 Specific example 540- 542 541- 543 AI24

3- cyclobutyl- 1- cyclohexyl- 4-(6- fluoropyridin- 3-yl)-1H- pyrazolo[3,4- b]pyridine- 6-carboxylic acid HP25, 351019- 18-6 J19 394 395 AI25

1-(4- fluorophenyl)- 4-(4- methoxy[1,4′- bipiperidin]- 1′-yl)-3- [(propan-2- yl)oxy]-1H- pyrazolo[3,4- b]pyridin-6- yl trifluoro- methane- sulfonate HP22 Specific example 615 617 AI26

1-(4- fluorophenyl)- 4-(4- methoxy[1,4′- bipiperidin]- 1′-yl)-3- [(propan-2- yl)oxy]-1H- pyrazolo[3,4- b]pyridine- 6- carbonitrile AI25 Specific example 492 493 AI27

3- cyclobutyl- 4-[4- (hydroxy- methyl) piperidin- 1-yl]-1- phenyl-1H- pyrazolo[3,4- b]pyridine- 6-carboxylic acid HP10 J10, Specific example 406 407 AI28

3- cyclobutyl- 4-(4- formyl- piperidin- 1-yl)-1- phenyl-1H- pyrazolo[3,4- b]pyridine- 6-carboxylic acid AI27 J20, Specific example 404 405 AI29

3- cyclobutyl- 1-(2- ethoxy- pyrimidin- 4-yl)-4-[4- (morpholin- 4- yl)piperidin- 1-yl]-1H- pyrazolo[3,4- b]pyridine- 6-carboxylic acid E422 Specific example 507

Lengthy table referenced here US20170101406A1-20170413-T00001 Please refer to the end of the specification for access instructions.

Lengthy table referenced here US20170101406A1-20170413-T00002 Please refer to the end of the specification for access instructions.

Determination of Biological Activity Cellular Assays Measuring CFTR Cell Surface Expression of CFTR-ΔF508 Using PathHunter® U2OS CFTR-ΔF508 Cells

The PathHunter® U2OS CFTR-ΔF508 cell assay (DiscoveRx) measures the expression of CFTR-ΔF508 at the plasma membrane. CFTR-ΔF508 has a folding defect leading to absence of protein at the plasma membrane. This assay is used to evaluate the capacity of compounds to increase the expression of CFTR-ΔF508 at the plasma membrane. The CFTR-ΔF508 is tagged with a ProLink™ peptide which can complement with plasma membrane expressed enzyme acceptor protein (EA-MEM). When both the ProLink™ and EA-MEM acceptor are in close proximity, i.e. both are located at the plasma membrane, a functional enzyme is formed of which the activity can be measured. The amount of CFTR-ΔF508 that can be rescued to the plasma membrane is correlated with the amount of functional enzyme that can be measured.

There are several ways to measure the capacity of compounds to rescue CFTR-ΔF508 to the plasma membrane; either compounds are evaluated on their own and the impact on plasma membrane levels is measured or compounds are evaluated in combination with a co-corrector, i.e. a compound that rescues CFTR-ΔF508 to the plasma membrane but rescue can be enhanced by addition of compounds due to a complementary mode of action.

Activity of Compounds in Combination with Co-Corrector:

For this purpose, PathHunter® U2OS CFTR-ΔF508 cells (DiscoveRx; custom made were cultured in AssayComplete™ U2OS Cell Culture medium (DiscoveRx; 92-0018GK3) as per manufacturer's instructions. For compound testing, cells were seeded in white 384-well plates (Greiner; 781080) at five thousand cells/well in 25 μL AssayComplete™ Cell Plating 5 Reagent (DiscoveRx; 93-0563R5A) and incubated overnight at 37° C., 5% CO₂. On day two, 5 μL of test compounds diluted in Cell Plating 5 Reagent were added to the cells with a final dimethyl sulfoxide (DMSO) concentration of 0.1%. In order to measure synergy with a co-corrector (3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-methoxy-3,4-dihydro-2H-chromen-2-yl]benzoic acid), 3 μM of co-corrector was added along with test compounds. All cell plates contained 3 μM of co-corrector or DMSO as positive and negative controls, respectively. Cells were incubated with compounds for twenty to twenty-four hours at 37° C., 5% CO₂. On day three, plates were placed at room temperature for thirty minutes and then 15 μL of substrate (PathHunter® Flash Detection Kit, DiscoveRx; 93-0247) was added per well. After one hour of incubation at room temperature in the dark, the luminescence signal was measured on a plate reader (Envision®, Perkin Elmer). Raw data were normalized to percentage activity values using the equation: 100×(Sample−Negative control)/(Positive control−Negative Control).

Activity of Compounds for their Intrinsic Corrector Capacity:

For this purpose PathHunter® U2OS CFTR-ΔF508 cells (DiscoveRx; custom made as described above) were cultured in AssayComplete™ U2OS Cell Culture medium (DiscoveRx; 92-0018GK3) as per manufacturer's instructions. For compound testing, cells were seeded in white 384-well plates (Greiner; 781080) at five thousand cells/well in 25 μL AssayComplete™ Cell Plating 5 Reagent (DiscoveRx; 93-0563R5A) and incubated overnight at 37° C., 5% CO₂. On day two, 5 μL of test compounds diluted in Cell Plating 5 Reagent were added to the cells with a final DMSO concentration of 0.1%. All cell plates contained 3 μM corrector (3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-methoxy-3,4-dihydro-2H-chromen-2-yl]benzoic acid) or DMSO as positive and negative controls, respectively. Cells were incubated with compounds for twenty to twenty-four hours at 37° C., 5% CO₂. On day three, plates were placed at room temperature for thirty minutes and then 15 μL of substrate (PathHunter® Flash Detection Kit, DiscoveRx; 93-0247) was added per well. After one hour of incubation at room temperature in the dark, the luminescence signal was measured on a plate reader (Envision®, Perkin Elmer). Raw data were normalized to percentage activity values using the equation: 100×(Sample−Negative control)/(Positive control−Negative Control).

Activity of Compounds in Presence of Human Serum

To evaluate the impact of plasma protein binding of compounds on their biological activity, the PathHunter® U2OS CFTR-ΔF508 assay was run in the presence of 40% human serum (Sigma; H4522). For this purpose PathHunter® U2OS CFTR-ΔF508 cells (DiscoveRx; custom made) were cultured in AssayComplete™ U2OS Cell Culture medium (DiscoveRx; 92-0018GK3) as per manufacturer's instructions. For compound testing, cells were seeded in white 384-well plates (Greiner; 781080) at five thousand cells/well in 25 μL AssayComplete™ Cell Plating 5 Reagent (DiscoveRx; 93-0563R5A) containing 40% human serum and incubated overnight at 37° C., 5% CO₂. On day two, 5 μL of test compounds diluted in Cell Plating 5 Reagent were added to the cells with a final DMSO concentration of 0.1%. All cell plates contained 3 μM corrector (4-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-methoxy-3,4-dihydro-2H-chromen-2-yl]benzoic acid) or DMSO as positive and negative controls respectively. Cells were incubated with compounds for twenty to twenty-four hours at 37° C., 5% CO₂. On day three, plates were placed at room temperature for thirty minutes, and then 15 μL of substrate (PathHunter® Flash Detection Kit, DiscoveRx; 93-0247) was added per well. After one hour of incubation at room temperature in the dark, the luminescence signal was measured on a plate reader (Envision®, Perkin Elmer). Raw data were normalized to percentage activity values using the equation: 100×(Sample−Negative control)/(Positive control−Negative Control).

Activity of Compounds in Presence of Human Serum

To evaluate the impact of plasma protein binding of compounds on their biological activity, the PathHunter® U2OS CFTR-ΔF508 was run in the presence of 40% human serum (Sigma; H4522). For this purpose PathHunter® U2OS CFTR-ΔF508 cells (DiscoveRx; custom made) were cultured in AssayComplete™ U2OS Cell Culture medium (DiscoveRx; 92-0018GK3) as per manufacturer's instructions. For compound testing, cells were seeded in white 384-well plates (Greiner; 781080) at five thousand cells/well in 25 μL AssayComplete™ Cell Plating 5 Reagent (DiscoveRx; 93-0563R5A) and incubated overnight at 37° C., 5% CO₂. On day two, the medium was replaced with 25 μL of primary human airway epithelial cell air-liquid interface medium or ALI medium, a 50:50 mixture of DMEM (Dulbecco's Modified Eagle Medium, Invitrogen; 41966-029) and LHC Basal Medium (Invitrogen; 12677-019) with additives as described in Table XVII) and containing 40% human serum. One hour later, 5 μL of test compounds diluted in ALI medium were added to the cells with a final DMSO concentration of 0.1%. All cell plates contained 3 μM corrector (4-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-methoxy-3,4-dihydro-2H-chromen-2-yl]benzoic acid) or DMSO as positive and negative controls respectively. Cells were incubated with compounds for twenty to twenty-four hours at 37° C., 5% CO₂. On day three, plates were placed at room temperature for thirty minutes and then washed twice with PBS (phosphate buffered saline) followed by the addition of 15 μL of substrate (PathHunter® Flash Detection Kit, DiscoveRx; 93-0247) per well. After one hour of incubation at room temperature in the dark, the luminescence signal was measured on a plate reader (Envision®, Perkin Elmer). Raw data were normalized to percentage activity values using the equation: 100×(Sample−Negative control)/(Positive control−Negative Control).

TABLE XVII Final concentration Ingredient in medium Provider Cat# BSA 0.5 mg/mL Sigma A7638 bovine pituitary 10 μg/mL Sigma P1476 extract Insulin 0.87 μM Sigma I9278 transferrin 0.125 μM Sigma T0665 hydrocortisone 0.21 μM Sigma H0396 triiodothyronine 0.01 μM Sigma T6397 Epinephrine 0.01 μM Sigma E4250 epidermal growth 5 ng/mL Invitrogen PHG0313 factor All-trans   5 × 10⁻⁸ M Sigma R-2625 retinoic acid o-Phosphoethanolamine 0.5 μM Sigma P-0503 ethanolamine 0.5 μM Sigma E0135 zinc sulfate 3.0 μM Sigma Z0251 (ZnSO4•7H2O) pen/strep 100 U/mL Sigma 15140-122 ferrous sulfate 1.5 × 10⁻⁶ M Sigma F8048 magnesium chloride   6 × 10⁻⁴ M Sigma M2670 hexahydrate calcium chloride 1.1 × 10⁻⁴ M Fluka 21097 dihydrate Trace elements: — sodium selenite 30 nM Sigma S5261 manganese chloride 1 nM Sigma M8054 tetrahydrate sodium metasilicate 500 nM Sigma S5904 nonahydrate ammonium molybdate 1 nM Sigma M1019 tetrahydrate ammonium metavanadate 5 nM Sigma 398128 nickel(II)sulfate 1 nM Fluka 72280 hexahydrate (Sigma) (N4882) tin(II) chloride 0.5 nM Sigma 243523 dihydrate

Measuring CFTR Cell Surface Levels Using HRP-Tagged AF508-CFTR Expressing CFBE Cells

The HRP-tagged AF508-CFTR cell assay measures the expression of CFTR-ΔF508 at the plasma membrane. CFTR-ΔF508 has a folding defect leading to absence of protein at the plasma membrane. This assay is used to evaluate the capacity of compounds to increase the expression of CFTR-ΔF508 at the plasma membrane. The CFTR-ΔF508 is tagged with HRP (horse radish peroxidase enzyme) within the ECL4 (Extracellular loop 4) of CFTR (Phuan, P.-W. et al. Synergy-based small-molecule screen using a human lung epithelial cell line yields AF508-CFTR correctors that augment VX-809 maximal efficacy. Mol. Pharmacol. 86, 42-51 (2014)). When HRP-tagged AF508-CFTR is present at the plasma membrane, the HRP enzyme activity can be measured. The amount of CFTR-ΔF508 that can be rescued to the plasma membrane is correlated with the amount of functional enzyme that can be measured.

There are several ways to measure the capacity of compounds to rescue CFTR-ΔF508 to the plasma membrane; either compounds are evaluated on their own and the impact on plasma membrane levels is measured or compounds are evaluated in combination with a co-corrector, i.e. a compound that rescues CFTR-ΔF508 to the plasma membrane but rescue can be enhanced by addition of compounds due to a complementary mode of action.

Activity of Compounds in Combination with Co-Corrector:

For this purpose doxycycline-inducible AF508-CFTR-HRP expressing CFBE4lo-cells (obtained from Gergely Lukacs, McGill University) were maintained in MEM (Minimum Essential Medium, Gibco; 31095) supplemented with 10% fetal bovine serum (Hyclone; SV30160.03) under puromycin (3 μg/mL) and G418 selection (0.2 mg/mL). For compound testing, cells were seeded at 4000 cells/well in white 384-well plates (Greiner; 781080) in 50 μL of medium containing 0.5 μg/mL doxycycline and incubated for 68 hours at 37° C., 5% CO₂. On day four, 10 μL of test compounds diluted in PBS (phosphate buffered saline) were added to the plates at a final DMSO concentration of 0.1%. In order to measure compound synergy with a co-corrector, 3 μM co-corrector (3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-methoxy-3,4-dihydro-2H-chromen-2-yl]benzoic acid) was added along with test compounds. All compound plates contained negative controls (DMSO) and positive controls (3 μM co-corrector). Cell plates were incubated at 33° C., 5% CO₂ for 20 hours. On day five, the cells were washed five times with phosphate-buffered saline, and HRP activity was assayed by the addition of 50 μL/well of HRP substrate (SuperSignal™ West Pico Chemiluminescent Substrate, Thermo Scientific; 34080). After incubation for 15 minutes in the dark, the chemiluminescence was measured using a plate reader (EnVision®, Perkin Elmer). Raw data were normalized to percentage activity values using the equation: 100×(Sample−Negative control)/(Positive control−Negative Control).

TABLE XVIII Illustrative EC₅₀ measured by CFTR cell surface levels using HRP-tagged ΔF508-CFTR expressing CFBE cells in the presence of a co-corrector. Compound # % Activation EC₅₀ (nM) 1 354.48 1040.5 2 198.6 2970 5 389.8 371 13 363.7 723 15 282.5 2600 17 272.5 1135 20 450.9 371 22 310.95 995.5 26 258.4 1088 32 399.6 1393 36 364.5 3340 40 340.8 392.5 41 301.2 526.9 43 360.8 371 47 390.5 566.6 50 313.2 2125 54 392.6 376.13 60 143.1 >10000 61 253.6 2349 62 349.9 1694.5 63 294.35 3340 64 113.3 >10000 65 258.2 2312 66 131.3 >10000 67 280.35 1256.5 68 274.9 1389 69 366.8 993.2 70 355.6 649 71 126.8 >10000 72 308.1 3340 73 303.9 3251 74 257.2 1484 75 254 1152 76 244.2 430.1 77 343.4 1111 78 132 >10000 79 256.45 5282.9 80 341.92 2932.5 81 398.25 570.45 82 335.65 971.45 83 332.65 1055 84 541.12 734.1 85 504.7 701.9 86 300.25 2552.5 87 148.9 3340 88 453.15 524.75 89 482.05 1238 90 367.15 882.75 91 176.6 3340 92 99.81 >10000 93 379.57 491.23 94 119.4 >10000 95 145.4 3340 96 329.75 1197.5 97 268 1158.8 98 350.65 833.7 99 247.8 1096 100 310 457.25 101 331.65 998.8 102 384 949.3 103 302 694.5 104 308.55 1006.2 105 383.25 878.75 106 237.45 2621.5 107 164.5 3340 108 329.7 752 109 398.15 752 110 397.65 536.5 111 299.8 423.85 112 378.1 2373.5 113 277 1168 114 460.85 1238.9 115 354 1277.5 116 262.7 3340 117 229.45 765.35 118 165.25 3340 119 413.2 624.2 120 231.45 3136.5 121 603.1 758.3 122 311.75 1767 123 267.95 2692 124 371.1 1884.5 125 351.8 1231 126 319.25 837.25 127 401.3 719.15 128 175.85 3340 129 380 390.35 130 430.55 407.38 131 388.7 620.05 132 156.4 3340 133 280.3 3340 134 362.2 556.4 135 355.55 1461.5 136 189.95 3340 137 158.05 3340 138 133.3 >10000 139 104.1 >10000 140 362.05 941.15 141 121.5 >10000 142 135.2 5555 143 246.8 2420 144 338.4 2617.5 145 368.6 850.1 146 134.9 >10000 147 318.9 830.55 148 238.75 3340 149 296 448.95 150 115.3 >10000 151 562.6 643.77 152 253.1 2090.5 153 386.85 1203 154 353.7 747.95 155 399.6 908.75 156 411.55 3163.5 157 621 485.15 158 112.2 >10000 159 415.33 754.8 160 544.87 329.33 161 333.87 794.67 162 399.73 807.87 163 554.5 422.6 164 608.5 375.3 165 533.35 515.3 166 241.5 3260 167 568.2 535 168 379.07 696.9 169 436.5 302.22 170 482.4 503.55 171 450.73 1065.3 172 513.1 480.25 173 380.52 2529.2 174 260.12 2538.5 175 522.6 531.9 176 619.28 448.45 177 606.47 689.27 178 591 458.3 179 548 977.65 180 524.85 686.75 181 397.95 1058.8 182 452.88 365.64 183 469.58 459.58 184 377.4 677.15 185 478.6 519.9 186 378.4 1260 187 522 564.95 188 432.9 498.7 189 590.78 292.3 190 301.85 634.32 191 375.1 481.28 192 439.45 273.5 193 402.32 424.72 194 233.9 1247 195 174.9 3340 196 520.8 596.25 197 445.2 432.45 198 364 1012 199 602.4 917.4 200 594.2 514.07 201 439.85 287.75 202 309.3 608.6 203 361.75 756.25 204 589.7 843.6 205 261.5 818.8 206 661.63 245.77 207 674.35 379.9 208 673.2 646.85 209 411.9 787 210 261 3340 211 289.75 1092.2 212 386.9 1490 213 456.97 382.5 214 323 608.85 215 347.15 915.3 216 431.7 1110 217 342.3 1468 218 380.9 932.5 219 474.5 365.25 220 470.77 369.23 221 645.97 283 222 612.47 268.17 223 484.45 686.6 224 396.65 895.65 225 395.7 901.4 226 352.2 1345.2 227 452.6 339.75 228 475.1 397.1 229 298 1559.6 230 507.3 514.3 231 625.45 569.55 232 380.95 1284.6 233 249.55 3340 234 510.27 367.63 235 403.1 743.15 236 423.62 637.92 237 372.97 324.1 238 613.4 539.75 239 495.85 712.85 240 609.05 515.7 241 259.75 2139.6 242 394.12 338.22 243 402.73 407.5 244 514.48 458.18 245 508.37 626.73 246 457.57 467.03 247 569.07 332.3 248 606.83 421.9 249 596.2 287.7 250 622.03 508.27 251 577.73 352.9 252 630.25 505.05 253 568.13 425 254 417.67 333.07 255 302.97 293.77 256 362.25 2051.5 257 440.2 787.9 258 364.3 918.7 259 673.9 1013.4 260 554.15 516.9 261 519.37 552.93 262 375.95 853.15 263 334.25 1134.5 264 428.47 463.45 265 397.8 1388.5 266 405.3 1048.3 267 498.35 412.25 268 425.68 393.9 269 452.33 390.9 270 430.4 529.05 271 323.5 395.87 272 319.6 3340 273 311.05 985.3 274 301.45 901.9 275 371.35 735.9 276 407.8 372.03 277 608.57 515.43 278 446.55 676.35 279 427.65 498.5 280 440.83 248.57 281 425.85 908.4 282 476.23 340.6 283 435.2 367.17 284 435.23 282.07 285 428 260.77 286 448.23 256.5 287 464.35 428.7 288 128 7505 289 172.8 1832.5 290 127.35 7505 291 349.55 1402.5 292 141.1 4175 293 264.9 2505 294 225.5 2505 295 172.1 2505 296 164 2505 297 184.07 3340 298 206.45 2439.5 299 194.8 2505 300 165 2505 301 117.35 7505 302 131.6 7505 303 123.5 7505 304 254.9 1987.5 305 170.5 1445 306 147.8 2505 307 233.4 1543.3 308 221.85 2505 309 237.3 1331.1 310 199.65 1605.5 311 195.5 2142.8 312 185 2319.5 313 132.2 7505 314 250.1 2505 315 150.3 4175 316 435.6 308.17 317 433.4 972.25 318 323.72 1860.5 319 270.75 4175 320 166.3 3340 321 196.85 2505 322 154.55 3340 323 128.4 >10000 324 279.1 2505 325 389.75 779.25 326 360.83 573.93 327 335.63 241.2 328 422.25 463.1 329 454.57 307 330 509.93 197.03 331 513.57 390.03 332 346.12 917.14 333 150.85 4105.5 334 226.6 1898 335 259.25 1382.5 336 297.8 1321.8 337 139.85 4175 338 135.7 7505 339 126.85 7505 340 146 4175 341 149.55 4093.5 342 138.5 3373 343 104.7 7505 344 218.25 1767 345 129.4 4175 346 151.2 4175 347 259.55 1408 348 410.3 369.93 349 382.73 236.33 350 397.5 316.33 351 256.6 1525 352 210.15 1431.5 353 438.65 458.55 354 429.9 322.8 355 360.63 556.2 356 331.9 428.35 357 274.8 805.67 358 370.47 205.65 359 349.55 2181 360 293 1033.6 361 227.65 1156.6 362 170.85 1803.5 363 187.2 2333 364 282.3 1638.7 365 278.05 1539 366 385.85 602.25 367 406.35 668.55 368 515.5 289.5 369 389.2 470.55 370 133 >10000 371 283.6 1105 372 388.6 126.5 373 306.9 303.95 374 297.35 463.5 375 184.1 1670 376 289.4 1138.8 377 295.65 1499.5 378 140.5 3340 379 128.5 5010 380 141.7 950.3 381 182.9 1670 382 268.1 1407 383 129.7 5010 384 123 5010 385 238.75 1670 386 250.65 1439.5 387 224.5 1670 388 171.6 1462.5 389 280.6 1287.6 390 362 271.6 391 528.7 374.43 392 519.35 323 393 454.3 313.7 394 392.57 676.97 395 480.35 549.05 396 409.8 301.15 397 217.3 298.75 398 275.7 737.23 399 336.55 475.25 400 283.65 980.15 401 306.07 653.43 402 214.5 1110 403 507.25 310.8 404 275.95 849.1 405 512.4 226.42 406 359.55 640.65 407 323.95 662.45 408 346.95 617.25 409 249.3 1110 410 317.5 227.6 411 456 976.05 412 387.2 307.4 413 392.2 337.9 414 295.15 372.7 415 334.35 248.95 416 369.5 784.95 417 322 317.8 418 342.25 597.6 419 293.9 508.9 420 411.25 289.05 421 368.65 722.9 422 336.05 1002.6 423 299.25 920.15 424 254.9 829.4 425 262.45 349.05 426 253.5 897.4 427 418.9 577.15 428 296 380.2 429 268.2 370.45 430 342.17 243.4 431 416.6 424.8 432 388.23 297.5 433 369.1 367.5 434 342.8 327.63 435 290.05 453.25 436 157.15 2505 437 419.53 795.4 438 507.27 387.16 439 312.85 1110 440 308.95 1931.5 441 289.75 1507 442 321.95 654.65 443 317.25 1474.5 444 282.8 542.85 445 127.85 >10000 446 171.35 3340 447 415.6 724.45 448 387.15 646.5 449 298.55 918.25 450 377.1 455.7 451 234.95 874.1 452 282.3 1110 453 275.35 655.8 454 470.3 636.35 455 421.5 451.75 456 414.5 335.3 457 430.85 392.25 458 399.6 278.1 459 319.8 379.8 460 322.2 327.85 461 328.05 342.85 462 316.85 318.3 463 341.85 373.2 464 328.25 407.65 465 244.6 703.45 466 271.1 1290 467 274.35 3340 468 297.2 370.5 469 360.3 716.05 470 311.25 427.15 471 259.9 2986 472 292.55 1384.6 473 280.9 545.4 474 301.35 2251.5 475 163.35 2716 476 297.8 385.85 477 266.3 500.5 478 292 409.4 479 317.77 1846 480 270.4 363.75 481 210.3 3045.5 482 284.7 708.77 483 267 366.85 484 226.6 369.35 485 242.05 334.75 486 299 335.15 487 316.5 490.65 488 261.9 462.25 489 274.95 769.75 490 311.1 296.3 491 256.5 965.53 492 239.55 2508.5 493 286.5 396.35 494 196.7 1159 495 235.15 307.4 496 145.5 2130.6 497 157.55 3340 498 435.9 87.785 499 435.6 199.84 500 289 296.05 501 367.65 353.45 502 327 1349 503 220.8 3192 504 138.9 >10000 505 118.3 >10000 506 137.7 >10000 507 218.3 2523 508 271.8 451 509 344.6 1668 510 313.2 397.4 511 214.6 1031 512 286.4 1417 513 349.6 472.1 514 178.2 3330 515 173.5 3330 516 275.5 723.2 517 303.2 575.1 518 237 530.9 519 340.6 3330 520 450.25 241.45 521 216.55 289.55 522 294.1 1079 523 320.1 630.3 524 354.25 261.05 525 311.3 936.3 526 284.5 370 527 291.2 1033 528 209.2 1939 529 126.7 >10000 530 254.15 542.4 531 223.4 1450 532 271.77 348.8 533 315.85 1227.5 534 281.95 893.2 535 205.9 1411 536 209.35 2467 537 191.2 3330 538 312.05 1538 539 564.8 197.67 540 314.05 323.6 541 287.85 799.2 542 290.6 1779 543 304.9 242.25 544 273 457.35 545 247.05 563 546 246.6 3330 547 318.7 1881 548 306 3330 549 467.2 61.66 550 122.4 >10000 551 424.35 87.225 552 396.65 396.25 553 419.05 118.55 554 365.83 1719.1 555 310.65 169.45 556 324 682.15 557 418.2 200.5 558 322.5 777.9 559 352.47 2050 560 437.33 171.23 561 348 426.7 562 347 920.97 563 272.97 2230 564 369.1 2453 565 319.8 1934.6 566 365.3 406.6 567 302.8 2112 568 279.9 2484 569 259.37 3063 570 254 3330 571 334.05 328.4 572 330.8 1190 573 376 299.2 574 469.5 189.63 575 431.9 208.7 576 390.78 396.45 577 300.47 1149.2 578 301.55 224.2 579 263.5 267.15 580 288 311.5 581 377.8 203.3 582 307.5 613.6 583 287.75 460.05 584 202.2 2882 585 245.3 2489 586 322.2 1999.8 587 360.33 2424.8 588 469.3 2422.5 589 451.75 303.45 590 310.45 2028.8 591 286.4 450.1 592 279 583.9 593 313.3 1166 594 269.8 621.4 595 383.8 206.8 596 299.4 522.1 597 342.5 229.9 598 274.4 3330 599 248.4 376.1 600 334.3 383.4 601 173.6 2484 602 393.4 133.8 603 273.3 869.7 604 292.2 255.75 605 531.3 43.56 606 199.7 1772 607 305.5 1980 608 338.1 683 609 336.4 1042 610 539.05 44.755 611 278.1 2933 612 266.9 1176.5 613 292 739.4 614 176.9 3330 615 216.65 2334 616 389.95 83.345 617 127.3 >10000 618 315.25 350.95 619 134.1 >10000 620 323.25 169.95 621 294.75 3144 622 275.2 67.53 623 308.3 501.2 624 281.85 2211 625 326.75 125.7 626 398.15 1008 627 126.25 >10000 628 217.7 3330 629 252.2 2161 630 323.7 254.35 631 283 177.2 632 129.55 >10000 633 279.27 713.53 634 294.7 2569 635 233.85 2114.5 636 391.3 790.05 637 174.45 3011 638 175.15 6665 639 261.7 1672.5 640 137.45 >10000 641 239.75 2269.5 642 281.95 2404 643 271.8 1261.5 644 196.3 3330 645 270.05 408.85 646 198 3330 647 301.3 2007.8 648 296.1 202.95 649 314.65 224.8 650 193.6 3330 651 187.9 2198 652 310.6 202.7 653 260.3 3330 654 245.5 3330 655 340.2 1128 656 415.7 190.6 657 543 305.7 658 345.9 455.25 659 424.5 69.535 660 284.47 3330 661 522.3 226.8 662 310.6 2301 663 315.5 90.88 664 120.6 >10000 665 330.43 1858.5 666 338.35 252.95 667 339.85 462 668 341.65 2361.5 669 315.5 795.4 670 397.3 218.25 671 357.4 942.85 672 343.15 552.95 673 163.25 3330 674 323.85 380.45 675 303.65 1054.8 676 164.55 892.2 677 260.45 6546.5 678 373.3 91.755 679 503.6 299.27 680 236.7 1362 681 373.05 197.3 682 368.9 115.95 683 600.53 60.673 684 384.65 235.8 685 510.3 245.15 686 431.1 237.4 687 454 89.717 688 532.6 246.9 689 329 802.75 690 318.25 2757.6 691 280.7 5000 692 381.4 931.25 693 392.45 324.6 694 421.9 534.7 695 385.5 118.5 696 346.8 1670 697 217.3 1273 698 242.7 745 699 432 169.03 700 290.9 128.1 701 498.5 36.07 702 214.1 1670 703 374.6 386 704 344.1 408.9 705 249.8 1670 706 284.4 488.2 707 326.3 341.2 708 314.8 147.3 709 223.9 1670 710 282.6 1350 711 248.8 1111 712 242.9 607.8 713 243.5 659.2 714 212.5 1408 715 261.4 1272 716 282.9 771.5 717 124.6 5000 718 209.8 1670 720 263.1 356.1 721 302.1 510.3 722 247 1670 723 344.8 1053 724 208.5 1670 725 173.2 868.7 726 409.6 311.3 727 348 1670 728 221.6 1670 729 530.4 1670 730 418.7 71.54 731 399.5 94.54 732 409.6 119.2 733 396.9 85.09 734 415 243.8 735 437.7 224.5 736 511.6 42.2 737 343.3 1670 738 472.1 110.5 739 327.2 1670 740 194.7 423.6 741 303 668.5 742 126.1 5000 743 330.5 1242 744 337.3 735.2 745 457.5 191.3 746 418.4 549.3 747 475.3 1670 749 387 277 750 394.1 502.8 751 400.2 1587 752 530.9 103.6 753 377.6 300.8 754 467.3 153 755 270.9 1670 756 446 401.1 757 489.6 402.2 758 139.5 811.6 759 207 1670 760 131.6 5000 761 284 1670 762 442.6 462.1 763 276.3 1670 764 255.65 2405 765 181.3 737.6 766 213.4 1182 767 210.1 1670 768 256.5 1670 769 157.2 1578 770 234.5 899.5 771 290.8 1670 772 226.6 1359 773 141.8 5000 774 375.6 1670 775 262.4 1670 776 261.4 531.4 777 254.9 955.3 778 149 1670 779 121.2 5000 780 429.5 124.4 781 368.7 1562 782 345.2 272.2 783 283.6 1670 784 225.6 1670 785 482.8 558.3 786 221.6 907 787 309.9 1295 788 329.4 1670 789 460.95 917.65 790 419.1 181.4 791 307.5 1670 792 321 709.9 793 363.5 1670 794 168.7 788.1 795 175.3 1670 796 358 1670 797 178.6 1670 798 186.5 863.6 799 306.6 1670 800 214.8 1488 801 253.1 1670 802 439.7 771.3 803 436 671.73 804 365 231.05 805 671 47.395 806 435.5 224.6 807 389.35 72.515 808 297 263.8 809 452.2 183.7 810 468.7 88.415 811 408.4 1078 816 359.9 67.64 817 384.9 46.36 819 313.1 3330 820 499.75 122.9 821 545.15 134.45 822 472.75 1136.6 823 375.2 146.85 824 535.65 277.05 825 455.85 143.95 826 528.15 101.81 827 453.25 92.96 828 518.35 47.94 829 411.7 344.4 830 588.2 63.15 831 402.5 406.7 832 526.6 1070 833 443.15 141.55 834 403 114.5 835 466.9 67.625 836 325.3 408.8 838 411.8 114.6 839 437.3 179.8 840 368.8 249.9 841 457.1 313.9 842 370 582.5 843 499.3 207.2 844 429.2 205.5 845 499.6 1085 846 495.1 968.1 847 503.8 286.2 848 405.2 427 849 458.6 230.61 850 615.6 88.86 851 559.8 123.3 852 391.4 3330 853 509.5 177.3 854 380.7 3330 855 490.9 87.15 856 416.9 88.31 857 232.2 2437 858 168.6 3175.5 859 291.4 2564 860 576.25 416.7 861 155.4 10000 862 359.6 636.15 863 320.9 369.93 864 458.6 105.33 865 306.8 1124.6 866 298.3 150.95 867 290.65 317.15 868 337.8 176.25 869 513.05 37.715 870 611.45 170.95 871 681.7 156.21 872 548.45 172 873 332.45 1845.2 874 608.35 83.045 875 450.3 819.25 876 562.35 267.15 877 374.57 605.13 878 391.3 99.645 879 446.25 196.18 880 446.95 693.2 881 242.75 699.85 882 363.85 371.85 883 380.9 238.1 884 377.6 213.75 885 255.5 2451.5 886 551.77 511 887 375.13 203.6 888 430 332.8 889 449.8 241.3 890 406.67 225.04 891 564.5 51.04 892 428.72 601.79 893 236.6 3330 894 371.3 218.25 895 429.4 3330 896 513.5 699.8 897 354.93 185.83 898 393.6 3330 899 351.9 308.7 900 389.73 216.03 901 432.3 150.6 902 411.75 114.25 903 480.55 108.4 904 372.85 101.82 905 466.55 144.85 906 485.34 72.824 907 483.65 182.62 908 486.75 171.25 909 498.4 56.175 910 499.9 79.065 911 405.9 73.96 912 397.9 267 913 531.4 163.25 914 429.25 172.95 915 587.95 50.215 916 362.05 1377 917 306.95 1670 918 352.1 479 919 416.35 255.65 923 263 380.46 924 609.82 136.48 925 126.05 10000 926 486.6 339.85 927 362.92 1104 928 362.2 2413 929 560 83.25 Activity of Compounds for their Intrinsic Corrector Capacity:

For this purpose doxycycline-inducible AF508-CFTR-HRP expressing CFBE4lo-cells (obtained from Gergely Lukacs, McGill University) were maintained in MEM (Gibco; 31095) supplemented with 10% fetal bovine serum (Hyclone; SV30160.03) under puromycin (3 μg/mL) and G418 selection (0.2 mg/mL). For compound testing, cells were seeded at 4000 cells/well in white 384-well plates (Greiner; 781080) in 50 μL medium containing 0.5 μg/mL doxycycline and incubated for 68 hours at 37° C., 5% CO₂. On day four, 10 μL test compounds diluted in PBS were added to the plates at a final DMSO concentration of 0.1%. All compound plates contained negative controls (DMSO) and positive controls (3 μM corrector, 3-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-methoxy-3,4-dihydro-2H-chromen-2-yl]benzoic acid). Cell plates were incubated at 33° C., 5% CO₂ for 20 hours. On day five, the cells were washed five times with phosphate-buffered saline, and HRP activity was assayed by the addition of 50 μL/well of HRP substrate (SuperSignal™ West Pico Chemiluminescent Substrate, Thermo Scientific; 34080). After incubation for 15 minutes in the dark, chemiluminescence was measured using a plate reader (EnVision®, Perkin Elmer). Raw data were normalized to percentage activity values using the equation: 100×(Sample−Negative control)/(Positive control−Negative Control).

TABLE XIX Illustrative EC₅₀ measured by CFTR cell surface levels using HRP-tagged ΔF508-CFTR expressing CFBE cells. Compound # % Activation EC₅₀ (nM) 1 151.61 1382.8 2 49.03 2653 3 46.83 3340 4 3.339 >10000 5 183.67 495.43 6 119.05 818.25 7 5.355 >10000 8 91.055 753.75 9 31.76 3340 10 116.55 866.85 11 134.3 1379 12 117.2 951.45 13 159.23 997.17 14 58.56 3340 15 98.68 2667 16 92.93 3340 17 99.207 2188.4 18 126.8 783 19 23.76 >10000 20 199.98 521.82 21 103.72 1057.8 22 131.28 1006.6 23 8.185 >10000 24 134.1 1829 25 93.1 1502 26 83.24 1272.5 27 41.145 6670 28 129.5 1176 29 146.1 3113 30 119.1 1206 31 96.335 521.8 32 176.7 637.62 33 90.265 1526.5 34 22.74 >10000 35 110.15 736.8 36 118.9 1996.3 37 112.9 1110 38 23.86 >10000 39 −2.469 >10000 40 154.82 537.03 41 110.52 957.1 42 74.83 3340 43 187.4 407.77 44 117.2 2202 45 5.851 >10000 46 15.23 >10000 47 183.2 608.4 48 163.7 988.7 49 107 1110 50 132.05 2801.8 51 41.22 1177 52 87.35 2679 53 72.97 3340 54 167.9 763.25 55 0.088 >10000 56 53.1 3340 57 68.57 3340 58 4.754 >10000 59 13.69 >10000 60 14.9 >10000 61 96.05 3340 62 159.65 2628.5 63 108.18 3340 64 3.754 >10000 65 103.02 3340 66 13.06 >10000 67 117.6 1593 68 106.65 1738 69 150.25 970 70 160.8 909.6 71 17.23 >10000 72 91.87 2246 73 110.1 3165 74 116.7 2560 75 117.1 3132 76 117.9 834.5 77 139.5 1172.1 78 10.784 >10000 79 195.9 696.6 80 184.8 611.45 81 193.6 744.4 82 135.95 1008.2 83 142.25 1467 84 289.83 829.22 85 314.6 919.7 86 129.75 3340 87 28.91 >10000 88 288.95 693.15 89 310.15 2529.5 90 169.65 1040 91 43.54 3340 92 2.873 >10000 93 175.6 679.6 94 3.061 >10000 95 16.66 >10000 96 141.5 1526 97 96.51 1525.5 98 165.8 1147 99 80.69 1528 100 115.7 980.9 101 143.75 1606 102 153 1044.8 103 115.65 703 104 130.4 1242.5 105 179.05 949.45 106 73 3340 107 20.98 >10000 108 145.5 904.35 109 235.9 885 110 212.25 705.05 111 110.34 458.7 112 200.55 2469 113 110.35 1668 114 251.05 805.95 115 152.3 1870.5 116 81.72 3340 117 70.77 1104 118 26.575 6670 119 207.25 915.35 120 70.235 3340 121 401.5 528.4 122 147.6 2991 123 107.95 3275.5 124 190.5 3077 125 168.75 1763 126 156.45 1693.5 127 221.4 1785.5 128 33.92 3340 129 178.3 414.25 130 237.68 488.98 131 153.75 899.4 132 13.45 >10000 133 74.96 3340 134 153.25 982.2 135 165.1 2195.5 136 40.405 3340 137 27.985 >10000 138 12.11 >10000 139 −0.041 >10000 140 178 1500 141 5.399 >10000 142 17.605 >10000 143 109.45 2285.5 144 212.6 2924.5 145 190.2 1432 146 8.92 >10000 147 114.65 1054 148 79.64 3340 149 112.95 652.6 150 6.341 >10000 151 322.03 354.5 152 75.36 2631 153 198.45 1526 154 153.9 918.2 155 203.65 1350.5 156 175.5 3340 157 388.2 459.35 158 1.521 >10000 159 150.16 736.56 160 318.83 446.77 161 111.83 921.17 162 147.97 992.4 163 232.43 525.1 164 359.9 675.07 165 350.4 793.55 166 68.01 3340 167 301.1 595.77 168 190.23 1291.2 169 217.88 448.36 170 208.6 737.7 171 199.67 1189 172 339.33 615.15 173 182.82 2946.5 174 90.21 3242.2 175 321.67 808.5 176 382.28 527.65 177 364.43 701.37 178 415 627.6 179 329.25 2820.5 180 249.55 971.55 181 149.2 1222.4 182 251.7 538.32 183 252.9 528.3 184 170.25 942.15 185 237.8 1110 186 168.7 1871 187 367.4 674 188 282.4 635.65 189 385.02 513.5 190 136.12 929 191 208.12 997.92 192 276.92 424.25 193 194.98 633.2 194 86.36 1712 195 27.46 >10000 196 251.45 555.4 197 219.25 644.35 198 220 1120 199 356.9 1223.7 200 330.83 437.77 201 251.3 596.3 202 136.8 794.8 203 162.5 842.95 204 402.1 1110 205 109 1110 206 466.87 323.13 207 384.15 581.4 208 413.75 603.35 209 165.6 1359 210 66.65 1176 211 94.07 2169.5 212 139.7 2638 213 247.33 678.73 214 154 819.8 215 165.95 1034.4 216 161 1014 217 129.7 1523 218 169.4 2305 219 248.7 517.6 220 245.37 786.37 221 429 314.83 222 429.93 433.47 223 246.95 714.3 224 189.6 1179 225 251.5 1984 226 189.05 3340 227 305.45 665.7 228 297.15 680.35 229 130.65 2145 230 368.85 1490 231 419 732.8 232 215.6 1684 233 72.33 3030.5 234 292.97 463.7 235 206.8 832 236 213.68 656 237 227 510.4 238 393.7 827.25 239 327.55 874.6 240 380.6 587.7 241 60.46 3340 242 206.5 603.32 243 224.73 659.6 244 320.17 472.95 245 267.15 777.45 246 212.75 463.5 247 390.27 419.9 248 405.93 550.1 249 410.6 474.72 250 394.7 456.23 251 389.2 438.27 252 398.4 698.4 253 375.87 655.73 254 234.6 611.4 255 120.77 441.57 256 180 3340 257 260.4 2532.5 258 169.7 1286 259 438.95 1129.8 260 326.4 783.6 261 314.07 702.33 262 164.4 915.6 763 161.25 1630.5 264 213.88 746.78 265 132.05 1245 266 197.55 1246.3 267 318.9 806.8 268 251.82 615.82 269 264.3 580.67 270 236.02 698.38 271 144.2 923.87 272 135.5 3340 273 100.16 1018.4 274 114.64 1078 275 173.8 923.1 276 206.93 503.93 277 356.47 513.03 278 259.1 990.85 279 257.8 900.5 280 238.6 485.4 281 226.7 1293.5 282 269.33 492.23 283 233.17 648.7 284 240.8 500.83 285 255.73 654.87 286 259.83 543.67 287 234.95 535.1 288 20.49 7505 289 46.35 2505 290 12.145 7505 291 168.85 1714 292 15.095 7505 293 90.275 2505 294 73.275 2505 295 46.475 2505 296 29.42 4175 297 50.78 2226.7 298 52.345 2505 299 51.845 2505 300 41.065 2505 301 12.64 7505 302 18.02 7505 303 10.878 7505 304 98.425 2505 305 29.97 3115.5 306 22.69 7505 307 77.423 1921 308 59.78 2505 309 67.305 1334.5 310 88.73 1892 311 53.7 2505 312 61.325 2505 313 11.239 7505 314 92.46 2505 315 24.61 3434 316 218.87 564.63 317 216.25 694.7 318 134.15 2626.5 319 80.905 2505 320 19.37 >10000 321 39.85 2505 322 12.25 >10000 323 8.143 >10000 324 93.32 2505 325 177.1 1197 326 180.53 976.93 327 176 368.7 328 196.9 671.3 329 239.4 557.63 330 326.43 405.1 331 311.73 1045.6 332 167.75 337 333 27.26 4175 334 36.645 4175 335 100.33 1610.5 336 118.2 1370 337 15.48 7505 338 12.64 7505 339 15.162 7505 340 18.86 7505 341 25.115 4175 342 19.4 7505 343 11.085 7505 344 69.225 2505 345 23.411 4175 346 20.555 7505 347 79.835 1413.5 348 217.2 553.33 349 208.2 460.07 350 211 425.8 351 84.055 1610.5 352 55.175 1511 353 224.1 506.5 354 212.07 450.5 355 180.03 740.4 356 152.8 489.45 357 113.47 885.07 358 205.07 410.5 359 142 2040.5 360 96.335 1166.6 361 80.015 1537.5 362 44.405 2029.5 363 56.625 2465 364 118.28 2277 365 147.55 2549 366 199.1 435.75 367 239.55 1008.8 368 357.3 520.6 369 251.6 843.25 370 19.18 >10000 371 116.35 1306.5 372 179 262.3 373 126.3 468.8 374 114.2 594.75 375 36.645 3340 376 109.7 1605.5 377 95.185 1670 378 14.56 5010 379 4.874 5010 380 14.735 5010 381 17.695 5010 382 80.645 1670 383 16.587 5010 384 8.1785 5010 385 54.89 1670 386 64.285 1307.6 387 65.365 1670 388 50.555 1670 389 101.73 1670 390 177.8 585.35 391 306.23 589.73 392 302 345.4 393 258.8 557.6 394 235.1 1493 395 223.6 437.7 396 209.3 403 397 73.11 644.65 398 96.49 1289.3 399 137.6 823.5 400 111.35 1346 401 136.97 1096.8 402 43.815 714.6 403 293.4 408.15 404 104.91 910.5 405 298.75 346.8 406 182.5 822.95 407 125.25 925.4 408 141.15 931.7 409 75.39 1073.5 410 155.63 557 411 280.85 3340 412 215.6 460.05 413 216.65 527.45 414 120.3 691.8 415 168.85 487.15 416 179.1 1254.5 417 134.8 545.75 418 144.95 1219.8 419 136 982.95 420 211.15 534.05 421 184.4 1292.5 422 131.9 1616 423 113.4 934.4 424 86.32 1075.6 425 123.35 990 426 76.06 998.1 427 200.4 663.35 428 128.05 977.7 429 114.95 979 430 175.73 372.53 431 198.57 542.6 432 197.97 560.57 433 185.45 628.95 434 154.17 580.67 435 116.7 773.3 436 24.16 4175 437 247.47 1225.5 438 277.03 330.87 439 120.85 1122 440 104.7 1922.5 441 111.85 2051 442 137.7 1075 443 146.9 2301 444 111.15 1108.4 446 20.695 >10000 447 243.3 1124.5 448 239.2 1075.2 449 139.3 1353 450 165.85 1089.9 451 71.425 1286.5 452 74.98 1110 453 110.68 716.15 454 253.5 997.9 455 288.4 1113.8 456 253.65 844.8 457 240.3 607.4 458 216.4 484.5 459 152.05 652.9 460 138.15 642.45 461 158.55 818.15 462 156.2 486.3 463 157.75 686.4 464 163.6 1144.5 465 91.04 1849.5 466 116.25 2327 467 97.95 3340 468 120.3 618.45 469 198.95 1121.2 470 147.5 735.55 471 106.45 3340 472 144 2493 473 102.9 1020.4 474 125.3 3340 475 35.755 6670 476 121.45 513.15 477 97.78 1018.5 478 125.2 828.05 479 114.41 1853.2 480 115.15 862.35 481 48.6 3340 482 144.75 1640 483 142.4 897.2 484 113.5 1110 485 107.5 1067 486 127 602.9 487 142.7 834.9 488 95.49 755 489 106.4 1859 490 144.95 399.65 491 82.97 2276.3 492 84.2 2370 493 129.05 644.7 494 65.56 3282 495 95.96 1110 496 32.84 3340 497 24.76 >10000 498 244.33 325.83 499 242.93 392.96 500 132.8 466.5 501 152.7 629.2 502 152 3340 503 65.78 3340 504 19.62 >10000 505 -6.616 >10000 506 40.12 3340 507 132.8 2167 508 104.6 1110 509 123.6 1241 510 99.8 1110 511 56.48 3340 512 103 1166 513 141.7 371 514 37.34 3340 515 15.59 >10000 516 123.4 1112 517 82.63 646.3 518 62.95 371 519 149.3 3340 520 213.9 583 521 58.57 487.8 522 114 478.7 523 136.2 2848 524 134.7 453.7 525 232.2 415.8 526 97.7 406.1 527 100.1 1162 528 80.74 3330 529 5.039 >10000 530 90.17 718.2 531 91.66 3330 532 107.05 707.25 533 114.5 3213 534 111 3330 535 56.68 2845 536 49.72 3330 537 45.36 3330 538 124.6 2431 539 366.3 370 540 142.2 452.1 541 120.7 987.9 542 104.6 1842 543 129.15 303.85 544 129.55 803.05 545 109.4 1146.4 546 87.52 3330 547 120.7 3330 548 88.93 2540 549 302.2 211 550 4.775 >10000 551 223.1 370 552 156.1 370 553 189.7 370 555 152 330.7 556 140.1 838.2 557 221.7 443.7 558 121.3 1374 560 265.05 393.05 561 174.8 1593 562 154.7 1765 566 150.5 387.6 571 189.6 812.2 573 149.7 974.4 574 294 479.5 575 268.4 512 576 175.2 495.95 577 108 3026 578 118.2 334.3 579 97.37 237.5 580 88.82 333.4 581 146 249.7 582 92.03 903 583 134.7 1017 587 149.5 3330 588 232.6 3330 589 232.15 457.5 590 141.3 2611 591 106.3 925.7 592 116.6 1159 594 75.66 786.8 595 162.8 347 596 99.54 735.2 599 81.59 357.3 602 159.3 256.3 603 92.66 1761 604 142.9 738.5 605 292.8 82.08 610 262.4 122.8 611 104.6 3330 612 109.5 3330 613 99.78 1596 614 32.02 3330 615 44.6 3330 616 144.2 116.5 617 7.139 >10000 618 105.9 546.6 619 7.484 >10000 620 147.4 249.5 621 89.46 3330 622 124.5 164.7 623 106.8 1158 624 98.14 3330 625 135.2 300.25 626 223.1 2713 627 9.221 >10000 628 67.69 3183 629 94.42 3330 630 136.15 308.05 631 99.143 345.9 632 18.94 >10000 633 66.87 665.5 634 122.2 3330 635 86.1 3330 636 184.1 617 637 49.14 3330 638 24.93 >10000 639 96.54 2211 640 13.97 >10000 641 65.07 3330 642 125.9 3330 643 95.84 2895 644 42.75 3330 645 111.55 1067.3 646 45.39 3330 647 119.9 2180 648 90.745 262.9 649 107.6 432.2 650 45.88 3330 651 54.22 3330 652 130.6 333.9 654 66.19 3330 655 165.6 3098 656 287.7 437.5 661 315 565 671 190.1 1609 672 141.6 748.5 674 158.5 520.8 675 118.8 658.8 676 35.03 5000 677 67.38 1573 678 181.5 230.4 679 279.5 370.2 681 220.95 408.5 682 172.9 180.1 683 395.1 140.7 684 230.2 380.2 685 260.5 164.2 686 240.4 1670 687 264.95 171.2 688 322.5 247.3 689 182.7 1568 690 136.1 1670 692 208.1 1670 693 185.9 1269 694 177.4 486.7 699 247.63 621.83 738 267.6 245.45 745 239.3 573.1 753 215 1028 754 254.1 385.3 757 208.45 318.8 764 85.92 3330 765 45.48 1670 766 54.3 1670 767 59.96 1670 768 79.69 1584 769 19.25 5000 770 85.33 1670 771 94.91 1670 772 53.82 1670 773 16.13 5000 774 163 1670 775 93.07 1670 776 113.2 1670 777 95 1670 778 9.442 5000 779 6.923 5000 780 233.5 249.2 781 154 1670 782 174.4 673.4 783 95.05 1670 784 38.94 1224 785 264.9 621.6 786 67.03 1165 787 121.5 770.7 788 115.7 1670 789 257.05 477.05 790 193.7 293.7 791 79.95 1670 792 170.1 1431 793 157.7 1670 794 58.82 1670 795 47.22 1670 796 169.7 1670 797 31.52 5000 798 58.3 1670 799 114 1670 800 45.22 1670 801 67.99 1670 802 218 462 803 229.35 1016.3 804 191.15 488.65 805 364 72.75 810 277.6 203.8 811 120.4 889.6 817 168 152.3 819 174.7 3330 820 351.3 284.6 822 272.3 300.7 823 188.7 258.2 824 338.9 179.6 825 289 207.3 826 314.4 156.9 827 265.4 257.2 828 283.5 83.17 829 170.7 381.1 830 353.9 115 831 231.3 1455 832 250.5 150.7 833 231.9 187.1 834 227.9 240.6 835 291.5 163.1 836 137.3 485.6 838 240.3 269.1 839 275.7 921 840 164.4 400.1 841 225 532.2 842 162.5 627.9 843 264.2 365.8 844 184.9 209.9 845 273.7 1465 846 317.9 874.2 847 279.1 539.5 848 249 1201 849 249.1 660.35 850 234.4 74.1 851 342.9 243.7 852 120.6 1714 853 290.9 261.3 854 131.1 2075 855 304.2 197.3 856 230.7 247.7 857 60.01 3330 858 29.24 10000 859 89.07 2232 860 383 516.9 861 31.08 10000 862 186.5 637.35 863 156.35 499.05 864 337.7 1007 865 146.9 439.5 866 99.71 277.4 867 125.2 1413 868 140.3 239.3 869 299.1 112.9 870 304.4 1037 871 355.1 275 872 368.7 591.4 873 139.8 3340 874 330.7 169.6 875 270.7 1598 876 324.4 300.6 877 162.65 347.55 878 181.05 221.4 879 279.6 355.2 880 259.5 168.6 883 160.6 329.7 884 140.6 298.5 885 66.2 3340 886 236.05 466.5 887 191.35 361.15 889 229.2 404.4 890 179 741.6 891 367.25 93.145 892 196.44 603.24 893 55.75 3142 894 164 304 895 178.2 1284 896 358.8 1634 897 151.25 348.45 898 231.6 3236 899 210.9 3096 900 183.97 432.57 901 199.2 87.56 902 193.9 229.9 903 275.8 331.2 904 200.1 236.65 905 278.8 362.4 906 276.92 145.54 907 270.7 259.7 908 220.2 256.2 909 277.7 134.1 910 286.2 186.7 911 222.45 189.85 912 212.4 720.2 913 326.3 1148 914 228.2 546 915 386.2 394.1 916 165.25 1670 917 116.67 1662.5 918 149.75 711.5 919 198.2 490.4 923 60.466 355.12 924 374.45 419.67 925 11.745 10000 926 240.2 520.75 927 150.78 1246.6 928 284.7 4031.5 929 474.3 181.1 930 434.3 240.3

YFP-Halide Influx Assay for the CFTR-ΔF508 Mutation

The YFP halide influx assay measures the functionality of the Cystic Fibrosis Transmembrane Conductance regulator (CFTR) channels in the cystic fibrosis bronchial epithelium cell line CFBE4lo-. The fluorescence of the yellow fluorescent protein (YFP) variant YFP H148Q, I152L or variant YFP H148Q, I152L & F47L is substantially quenched by iodine, a halide that is efficiently transported by CFTR. The assay is thus used to evaluate the effect of corrector compounds on CFTR channel function by measuring the extent of YFP signal quenching. (Galietta, L. J. V., Haggie, P. M., Verkman, A. S., 2001. Green fluorescent protein-based halide indicators with improved chloride and iodide affinities. FEBS Lett. 499, 220-224. doi: 10.1016/S0014-5793(01)02561-3; Nagai, T., Ibata, K., Park, E. S., Kubota, M., Mikoshiba, K., Miyawaki, A., 2002. A variant of yellow fluorescent protein with fast and efficient maturation for cell-biological applications. Nat. Biotechnol. 20, 87-90. doi:10.1038/nbt0102-87). For this purpose, CFBE4lo-cells were seeded in 96-well plates (6000 CFBE cells/well). One day after seeding, the CFBE cells were transduced with adenoviral vectors that direct the expression of the CFTR ΔF508 mutant and of the YFP reporter. Cells were treated with test compounds for 24 hours at 37° C. to allow trafficking of corrected CFTR to the membrane. The next day the CFTR channels were activated by treatment with the cAMP inducer forskolin (10.67 μM) and potentiator, N-(3-carbamoyl-5,5,7,7-tetramethyl-4,7-dihydro-5H-thieno[2,3-c]pyran-2-yl)-1H-pyrazole-5-carboxamide (0.5 μM), in 1×D-PBS (from Gibco, Cat n#14090-091) for 20 minutes prior to addition of an I⁻ solution (137 mM NaI, 2.7 mM KI, 1.76 mM KH₂PO₄, 10.1 mM Na₂HPO₄, 5 mM glucose). The F induced quenching of fluorescence is recorded immediately after injection of for 7 seconds. The capacity of a compound to increase number of channels, and therefore overall halide influx is directly correlated with the decrease in fluorescence, and is expressed as (1-(fluorescence after 7 seconds (F)/fluorescence before injection (F0))) and an EC₅₀ can be derived from a (1-F/F0) vs compound concentration plot.

TECC Assay Primary Bronchial Epithelial Cells Protocol

The TECC (Tranepithelial Clamp Circuit, EP-design) assay measures the functionality of the cystic fibrosis Transmembrane Conductance regulator (CFTR) by measuring the short circuit current (Isc) generated over the basolateral and apical membrane of lung epithelial cells. In TECC the transepithelial potential PD and transepithelial resistance (Rt)) are measured in an open circuit and transformed to Ieq using Ohm's law. 24 Wells can be measured simultaneously allowing a higher throughput compared to Ussing chambers.

For this purpose, bronchial epithelial cells isolated from CF patients homozygous for the CFTR ΔF508 mutation (hAEC-CF, Epithelix, Geneva, Switzerland; McGill University, Montreal, Qc; Asterand, Detroit, Mich.; University of North Carolina, Chapel Hill, N.C.) are plated on type IV collagen-coated Transwell® supports (Costar). Human airway epithelia are generated by provision of an air-liquid interface for 21 days to form well-differentiated polarized cultures that resemble in vivo pseudo-stratified ciliated epithelium (Fulcher, M. L., Gabriel, S., Burns, K. A., Yankaskas, J. R., Randell, S. H., 2005. Well-differentiated human airway epithelial cell cultures. Methods Mol. Med. 107, 183-206). The differentiated cells are treated with test corrector compound(s) (corrector alone or in combination with co-corrector, 4-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-methoxy-3,4-dihydro-2H-chromen-2-yl]benzoic acid (G924806/A-1618261) (“acute”) or test corrector compounds, co-corrector and potentiator, N-(3-carbamoyl-5,5,7,7-tetramethyl-4,7-dihydro-5H-thieno[2,3-c]pyran-2-yl)-1H-pyrazole-5-carboxamide GLPG1837, (“chronic”) for 24 hours basolaterally to allow sufficient expression of properly folded CFTR protein on the membrane. All compound plates contained negative controls (DMSO) and positive controls. All compound plates contained negative controls (DMSO) and positive controls (0.15 μM, 4-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-(difluoromethoxy)-3,4-dihydro-2H-chromen-2-yl]benzoic acid).

For electrophysiological recording of the “acute” experiments, the human airway epithelia are mounted in the TECC heating plate and kept at 37° C. The epithelia are bathed in a NaCl-Ringer solution (120 mM NaCl, 25 mM NaHCO₃, 1.2 mM CaCl₂, 1.2 mM MgCl₂, 0.8 mM KH₂PO₄, 0.8 mM K₂HPO₄, pH 7.4, 5 mM glucose) on both the basolateral and apical sides. Apical amiloride is used to inhibit the endogenous epithelial sodium channel (ENaC) currents while forskolin is applied on both apical and basolateral side to stimulate CFTR. CFTR activity is measured by addition of forskolin followed by addition of a potentiator, N-(3-carbamoyl-5,5,7,7-tetramethyl-4,7-dihydro-5H-thieno[2,3-c]pyran-2-yl)-1H-pyrazole-5-carboxamide, on both sides. Measurements are done during a 20 minute timeframe with recordings every 2 minutes. The increase in I_(eq) is used as a measure for the increased CFTR activity, EC₅₀ values can be generated by measuring impact of different concentrations of compound on I_(eq) on primary cells, for this purpose each transwell is treated with a different compound concentration for 24 hours. Inhibitor-172, an inhibitor specific for CFTR, is used to test the specificity of the tested compounds. Raw data were normalized to percentage activity values using the equation: 100×(Sample−Negative control)/(Positive control−Negative Control).

TABLE XX Illustrative acute TECC assay response with and without the presence of a co-corrector. Compound % Activity at % Activity at 3 μM # 10 μM (I_(eq)*) with co-corrector (I_(eq))  89 147.6 123 100.6 151 100.6 169 279.1 213 199.4 220 122.9 222 221.3 *I_(eq) refers to calculations based on the maximum current.

For electrophysiological recording of the “chronic” experiments, the human airway epithelia are mounted in the TECC heating plate for electrophysiological measurement and kept at 37° C. The epithelia are bathed in a NaCl-Ringer solution (120 mM NaCl, 25 mM NaHCO₃, 1.2 mM CaCl₂, 1.2 mM MgCl₂, 0.8 mM KH₂PO₄, 0.8 mM K₂HPO₄, pH 7.4, 5 mM glucose) on both the basolateral and apical sides. Test compounds (corrector, co-corrector, 4-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-(difluoromethoxy)-3,4-dihydro-2H-chromen-2-yl]benzoic acid, and potentiator, N-(3-carbamoyl-5,5,7,7-tetramethyl-4,7-dihydro-5H-thieno[2,3-c]pyran-2-yl)-1H-pyrazole-5-carboxamide), are re-added to the recording solution prior to measurement. Apical amiloride is used to inhibit the endogenous ENaC currents while forskolin is applied on both apical and basolateral side to stimulate CFTR. Measurements are done during a 20 minute timeframe with recordings every 2 minutes. The increase in I_(eq) is used as a measure for the increased CFTR activity, EC₅₀ values can be generated by measuring impact of different concentrations of compound on I_(eq) on primary cells, for this purpose each transwell is treated with a different compound concentration. Inhibitor-172, an inhibitor specific for CFTR, is used to test the specificity of the tested compounds. Raw data were normalized to percentage activity values using the equation: 100×(Sample−Negative control)/(Positive control−Negative Control).

TABLE XXI Illustrative chronic TECC assay response. % % % Activity EC₅₀ Activity Activity EC₅₀ Compound at 1 μM (nM) at 1 μM at 3 μM (nM) # (I_(eq)*) (I_(eq)) (AUC**) (AUC) (AUC) 191 220 50 192 235 <30 201 254 <30 204 241 <30 205 140 >1000 213 390 >300 220 720 120 227 300 30 228 280 <30 244 210 <30 268 267 25 456 120 539 557 557 262 384 560 <30 574 190 575 290 100 576 183 610 471 656 48 657 78 679 373.3333 28 683 196.675 687 263.3333 53.52 699 162 738 230 23.01 754 190 789 235 790 220 120.3 803 161.4501 804 290 809 186.6667 810 191.4768 849 256.6667 15.6 878 170 886 282.5409 887 273.3871 1340 890 366.6667 892 188.3291 900.1 894 300 897 375 898 150.7853 2639 910 531.5026 915 423.3333 924 235.9027 10.56 927 1936 *I_(eq) refers to calculations based on the maximum current. **AUC is the full area under the curve upon forskolin stimulation.

Information on protein binding of compounds can be retrieved from incubation of compounds in the presence of 40% human serum. For this purpose the differentiated cells are treated basolaterally with test compounds in medium containing 40% human serum (Sigma; H4522) for 24 hours. For electrophysiological recording, the human airway epithelia are mounted in the TECC heating plate and kept at 37° C. The epithelia are bathed in a NaCl-Ringer solution (120 mM NaCl, 25 mM NaHCO₃, 1.2 mM CaCl₂, 1.2 mM MgCl₂, 0.8 mM KH₂PO₄, 0.8 mM K₂HPO₄, pH 7.4, 5 mM glucose) on both the basolateral and apical sides. Test compounds (corrector, co-corrector, 4-[(2R,4R)-4-({[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl}amino)-7-(difluoromethoxy)-3,4-dihydro-2H-chromen-2-yl]benzoic acid, and potentiator, N-(3-carbamoyl-5,5,7,7-tetramethyl-4,7-dihydro-5H-thieno[2,3-c]pyran-2-yl)-1H-pyrazole-5-carboxamide), are re-added to the recording solution prior to measurement. Apical amiloride is used to inhibit the endogenous ENaC currents while forskolin is applied on both apical and basolateral side to stimulate CFTR. Measurements are done during a 20 minute timeframe with recordings every 2 minutes. The increase in I_(eq) is used as a measure for the increased CFTR activity, EC₅₀ values can be generated by measuring impact of different concentrations of compound on I_(eq) on primary cells, for this purpose each transwell is treated with a different compound concentration. Inh-172, an inhibitor specific for CFTR, is used to test the specificity of the tested compounds.

It is understood that the foregoing detailed description and accompanying examples are merely illustrative and are not to be taken as limitations upon the scope of the invention, which is defined solely by the appended claims and their equivalents. Various changes and modifications to the described embodiments will be apparent to those skilled in the art. Such changes and modifications, including without limitation those relating to the chemical structures, substituents, derivatives, intermediates, syntheses, formulations, or methods, or any combination of such changes and modifications of use of the invention, may be made without departing from the spirit and scope thereof.

LENGTHY TABLES The patent application contains a lengthy table section. A copy of the table is available in electronic form from the USPTO web site (http://seqdata.uspto.gov/?pageRequest=docDetail&DocID=US20170101406A1). An electronic copy of the table will also be available from the USPTO upon request and payment of the fee set forth in 37 CFR 1.19(b)(3). 

We claim:
 1. A compound of formula (I) or a pharmaceutically acceptable salt thereof,

wherein R¹ is G^(1A), -G^(1B)-G^(1C), -G^(1B)-L^(1A)-G^(1C), C₁-C₆ haloalkyl, C₁-C₆ alkyl, —(C₁-C₆ alkylenyl)-CN, —(C₁-C₆ alkylenyl)-G^(1D), or -G^(1D)-O-benzyl; L^(1A) is —O— or —O—(C₁-C₃ alkylenyl)-; wherein the left end of the L^(1A) moiety is attached to G^(1B); G^(1A) is phenyl, aryl, 5-6 membered monocyclic heteroaryl, 4-7 membered monocyclic heterocycle, fused bicyclic heterocycle, or C₃-C₆ monocyclic cycloalkyl; wherein each G^(1A) is optionally substituted with 1, 2, 3, or 4 independently selected R^(1a) groups; G^(1B) is phenyl or 5-6 membered monocyclic heteroaryl; wherein each G^(1B) is optionally substituted with 1, 2, 3, or 4 independently selected R^(1b) groups; G^(1C) is 4-7 membered monocyclic heterocycle which is optionally substituted with 1, 2, 3, or 4 independently selected R^(1c) groups; G^(1D), at each occurrence, is a 4-7 membered monocyclic heterocycle, 5-6 membered monocyclic heteroaryl, or a C₃-C₆ monocyclic cycloalkyl; wherein each G^(1D) is optionally substituted with 1, 2, 3, or 4 independently selected R^(1d) groups; R² is C₂-C₄ alkenyl, C₁-C₆ alkyl, C₁-C₆ haloalkyl, —OR^(2xa), —(C₁-C₆ alkylenyl)-OR^(2xb), —(C₁-C₆ alkylenyl)-N(R^(2xb))₂, —C(O)OR^(2xb), —C(O)N(R^(2xb))₂, or -G^(2A); R^(2xa) is hydrogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, or G^(2B); R^(2xb), at each occurrence, is independently hydrogen, C₁-C₆ alkyl, or C₁-C₆ haloalkyl; G^(2A) and G^(2B) are each independently 4-7 membered monocyclic heterocycle or C₃-C₆ monocyclic cycloalkyl; wherein G^(2A) and G^(2B) are each optionally substituted with 1, 2, or 3 independently selected R^(2a) groups; R³ is halogen, G^(3A), -G^(3B)-L¹-G^(3C), -G^(3B)-L³-G^(3C)-L⁴-G^(3F), —(C₁-C₆ alkylenyl)-G^(3E), —OR^(3a), —N(R^(3a))(R^(3b)), —N(R^(3b))C(O)G^(3D), or —C(O)G^(3D); R^(3a), at each occurrence, is independently G^(3E), C₁-C₆ haloalkyl, or C₁-C₆ alkyl; wherein the C₁-C₆ haloalkyl and the C₁-C₆ alkyl are each optionally substituted with one or two substituents independently selected from the group consisting of G^(3E), —OR^(3xa), —C(O)G^(3D), —N(R^(3xb))₂, and —S(O)₂R^(3xc); R^(3xa), R^(3xb), and R^(3xc), at each occurrence, are each independently hydrogen, C₁-C₆ haloalkyl, C₁-C₆ alkyl, G^(3E), —(C₁-C₆ alkylenyl)-OR^(3ya), or —(C₁-C₆ alkylenyl)-N(R^(3ya))₂; wherein R^(3ya), at each occurrence, is independently hydrogen, C₁-C₆ alkyl, or C₁-C₆ haloalkyl; R^(3b), at each occurrence, is hydrogen, C₁-C₆ alkyl, or C₁-C₆ haloalkyl; L¹ is a bond, C₁-C₆ alkylenyl, (C₁-C₆ alkylenyl)_(r)-L²-(C₁-C₆ alkylenyl)_(s), or O—(C₁-C₆ alkylenyl)-C(O), wherein the left end of the L¹ moiety is attached to G^(3B); L² is O, N(R^(x)), C(O), N(R^(x))C(O), or C(O)N(R^(x)); wherein each R^(x) is independently hydrogen, C₁-C₆ alkyl, or C₁-C₆ haloalkyl; L³ is a bond or C₁-C₆ alkylenyl; L⁴ is a bond, C₁-C₆ alkylenyl, O, N(R^(2x)), C(O), N(R^(2x))C(O), or C(O)N(R^(2x)); wherein each R^(2x) is independently hydrogen, C₁-C₆ alkyl, or C₁-C₆ haloalkyl; r is 0 or 1; s is 0 or 1; G^(3A), G^(3B), and G^(3C), are each independently C₃-C₁₁ cycloalkyl, phenyl, 5-6 membered monocyclic heteroaryl, or 4-11 membered heterocycle, wherein G^(3A), G^(3B), and G^(3C) are each optionally substituted with 1, 2, 3, or 4 independently selected R^(e) groups; G^(3D), at each occurrence, is 4-7 membered monocyclic heterocycle which is optionally substituted with 1, 2, 3, or 4 independently selected R^(e) groups; G^(3E), at each occurrence, is independently C₃-C₈ monocyclic cycloalkyl or 4-11 membered heterocycle; wherein each G^(3E) is optionally substituted with 1, 2, 3, or 4 substituents independently selected from the group consisting of R^(e) and G^(3F); G^(3F), at each occurrence, is independently a 4-7 membered monocyclic heterocycle or a C₃-C₆ monocyclic cycloalkyl; wherein each G^(3F) is optionally substituted with 1, 2, 3, or 4 independently selected R^(e) groups; R^(e), at each occurrence, is independently C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₁-C₆ alkyl, C₁-C₆ haloalkyl, halogen, oxo, —CN, —N₃, NO₂, —OR^(f), —OC(O)R^(g), —OC(O)NR^(f)R^(h), —SR^(f), —S(O)₂R^(f), —S(O)₂NR^(f)R^(h), —C(O)R^(f), —C(O)OR^(f), —C(O)NR^(f)R^(h), —C(O)N(R^(h))S(O)₂R^(f), —N(R^(f))₂, —N(R^(h))C(O)R^(f), —N(R^(h))S(O)₂R^(g), —N(R^(h))C(O)O(R^(g)), —N(R^(h))C(O)NR^(f)R^(h), or —N(R^(h))S(O)₂NR^(f)R^(h); wherein the C₁-C₆ haloalkyl and the C₁-C₆ alkyl are each optionally substituted with 1 or 2 substituents independently selected from the group consisting of halogen, —CN, NO₂, —OR^(f), —OC(O)R^(g), —OC(O)NR^(f)R^(h), —SR^(f), —S(O)₂R^(f), —S(O)₂NR^(f)R^(h), —C(O)R, —C(O)OR, —C(O)NR^(f)R^(h), —C(O)N(R^(h))S(O)₂R^(f), —N(R^(f))₂, —N(R^(h))C(O)R^(f), —N(R^(h))S(O)₂R^(g), —N(R^(h))C(O)O(R^(g)), —N(R^(h))C(O)NR^(f)R^(h), and —N(R^(h))S(O)₂NR^(f)R^(h); R^(f), at each occurrence, is independently hydrogen, C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₁-C₆ haloalkyl, —(C₁-C₆ alkylenyl)-CN, —(C₁-C₆ alkylenyl)-OR^(m), —(C₁-C₆ alkylenyl)-OC(O)R^(n), —(C₁-C₆ alkylenyl)-OC(O)N(R^(m))₂, —(C₁-C₆ alkylenyl)-SR^(m), —(C₁-C₆ alkylenyl)-S(O)₂R^(m), —(C₁-C₆ alkylenyl)-S(O)₂N(R^(m))₂, —(C₁-C₆ alkylenyl)-C(O)R^(m), —(C₁-C₆ alkylenyl)-C(O)OR^(m), —(C₁-C₆ alkylenyl)-C(O)N(R^(m))₂, —(C₁-C₆ alkylenyl)-C(O)N(R^(m))S(O)₂R^(n), —(C₁-C₆ alkylenyl)-N(R^(m))₂, —(C₁-C₆ alkylenyl)-N(R^(m))C(O)R^(n), —(C₁-C₆ alkylenyl)-N(R^(m))S(O)₂R^(n), —(C₁-C₆ alkylenyl)-N(R^(m))C(O)O(R^(n)), —(C₁-C₆ alkylenyl)-N(R^(m))C(O)N(R^(m))₂, or —(C₁-C₆ alkylenyl)-N(R^(m))S(O)₂N(R^(m))₂; R^(g), at each occurrence, is independently C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₁-C₆ haloalkyl, —(C₁-C₆ alkylenyl)-CN, —(C₁-C₆ alkylenyl)-OR^(m), —(C₁-C₆ alkylenyl)-OC(O)R^(n), —(C₁-C₆ alkylenyl)-OC(O)N(R^(m))₂, —(C₁-C₆ alkylenyl)-SR^(m), —(C₁-C₆ alkylenyl)-S(O)₂R^(m), —(C₁-C₆ alkylenyl)-S(O)₂N(R^(m))₂, alkylenyl)-C(O)R^(m), —(C₁-C₆ alkylenyl)-C(O)OR^(m), —(C₁-C₆ alkylenyl)-C(O)N(R^(m))₂, —(C₁-C₆ alkylenyl)-C(O)N(R^(m))S(O)₂R^(n), —(C₁-C₆ alkylenyl)-N(R^(m))₂, —(C₁-C₆ alkylenyl)-N(R^(m))C(O)R^(n), —(C₁-C₆ alkylenyl)-N(R^(m))S(O)₂R^(n), —(C₁-C₆ alkylenyl)-N(R^(m))C(O)O(R″), —(C₁-C₆ alkylenyl)-N(R^(m))C(O)N(R^(m))₂, or —(C₁-C₆ alkylenyl)-N(R^(m))S(O)₂N(R^(m))₂; R^(h), at each occurrence, is independently hydrogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, or —(C₁-C₆ alkylenyl)-OR^(m); R^(1a), R^(1b), R^(1c), R^(1d), and R^(2a), at each occurrence, are each independently C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, halogen, C₁-C₆ haloalkyl, oxo, —CN, NO₂, —OR^(m), —OC(O)R^(n), —OC(O)N(R^(m))₂, —SR^(m), —S(O)₂R^(m), —S(O)₂N(R^(m))₂, —C(O)R^(m), —C(O)OR^(m), —C(O)N(R^(m))₂, —C(O)N(R^(m))S(O)₂R^(n), —N(R^(m))₂, —N(R^(m))(alkoxyalkyl), —N(alkoxyalkyl)₂, —N(R^(m))C(O)R^(n), —N(R^(m))S(O)₂R^(n), —N(R^(m))C(O)O(R^(n)), —N(R^(m))C(O)N(R^(m))₂, —N(R^(m))S(O)₂N(R^(m))₂, —(C₁-C₆ alkylenyl)-CN, —(C₁-C₆ alkylenyl)-OR^(m), —(C₁-C₆ alkylenyl)-OC(O)R^(n), —(C₁-C₆ alkylenyl)-OC(O)N(R^(m))₂, —(C₁-C₆ alkylenyl)-SR^(m), —(C₁-C₆ alkylenyl)-S(O)₂R^(m), —(C₁-C₆ alkylenyl)-S(O)₂N(R^(m))₂, —(C₁-C₆ alkylenyl)-C(O)R^(m), —(C₁-C₆ alkylenyl)-C(O)OR^(m), —(C₁-C₆ alkylenyl)-C(O)N(R^(m))₂, —(C₁-C₆ alkylenyl)-C(O)N(R^(m))S(O)₂R^(n), —(C₁-C₆ alkylenyl)-N(R^(m))₂, —(C₁-C₆ alkylenyl)-N(R^(m))C(O)R^(n), —(C₁-C₆ alkylenyl)-N(R^(m))S(O)₂R^(n), —(C₁-C₆ alkylenyl)-N(R^(m))C(O)O(R^(n)), —(C₁-C₆ alkylenyl)-N(R^(m))C(O)N(R^(n))₂, or —(C₁-C₆ alkylenyl)-N(R^(m))S(O)₂N(R^(n))₂; R^(m), at each occurrence, is independently hydrogen, C₁-C₆ alkyl, or C₁-C₆ haloalkyl; R^(n), at each occurrence, is independently C₁-C₆ alkyl or C₁-C₆ haloalkyl; and R⁴ is hydrogen, C₁-C₃ alkyl, or C₁-C₃ haloalkyl; with the proviso that when R¹ is C₁-C₆ alkyl or G^(1A), wherein G^(1A) is optionally substituted phenyl, optionally substituted 5-6 membered monocyclic heteroaryl, or optionally substituted 4-7 membered monocyclic heterocycle, R² is C₁-C₆ alkyl, and R³ is G^(3A), then G^(3A) is not optionally substituted phenyl or optionally substituted 5-6 membered monocyclic heteroaryl.
 2. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R¹ is G^(1A), -G^(1B)-G^(1C), C₁-C₆ haloalkyl, or C₁-C₆ alkyl.
 3. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R¹ is G^(1A).
 4. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R¹ is -G^(1B)-G^(1C).
 5. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R² is C₂-C₄ alkenyl, C₁-C₆ alkyl, C₁-C₆ haloalkyl, —OR^(2xa), or G^(2A).
 6. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R² is C₁-C₆ alkyl, C₁-C₆ haloalkyl, or G^(2A).
 7. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R³ is G^(3A), -G^(3B)-L¹-G^(3C), —OR^(3a), or —N(R^(3a))(R^(3b)).
 8. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R¹ is G^(1A) or -G^(1B)-G^(1C); and R² is C₂-C₄ alkenyl, C₁-C₆ alkyl, C₁-C₆ haloalkyl, —OR^(2xa), or G^(2A).
 9. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R¹ is G^(1A) or G^(1B)-G^(1C); and R³ is G^(3A), -G^(3B)-L¹-G^(3C), —OR^(3a), or —N(R^(3a))(R^(3b)).
 10. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R¹ is G^(1A) or -G^(1B)-G^(1C); R² is C₂-C₄ alkenyl, C₁-C₆ alkyl, C₁-C₆ haloalkyl, —OR^(2xa), or G^(2A); and R³ is G^(3A), -G^(3B)-L¹-G^(3C), —OR^(3a), or —N(R^(3a))(R^(3b)).
 11. The compound of claim 10 or a pharmaceutically acceptable salt thereof, wherein G^(1A) is optionally substituted phenyl or optionally substituted 5-6 membered monocyclic heteroaryl; R² is C₁-C₆ alkyl; and G^(3A) is an optionally substituted 4-11 membered heterocycle.
 12. The compound of claim 10 or a pharmaceutically acceptable salt thereof, wherein G^(1A) is optionally substituted phenyl or optionally substituted 5-6 membered monocyclic heteroaryl; R² is —OR^(2xa) or G^(2A); and R^(2xa) is G^(2B).
 13. The compound of claim 12 or a pharmaceutically acceptable salt thereof, wherein R² is G^(2A); and G^(2A) is optionally substituted C₃-C₆ monocyclic cycloalkyl.
 14. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R¹ is G^(1A) or -G^(1B)-G^(1C); R² is C₁-C₆ alkyl or G^(2A); and R³ is G^(3A), -G^(3B)-L¹-G^(3C), or —OR^(3a).
 15. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R¹ is G^(1A); G^(1A) is optionally substituted phenyl or optionally substituted 5-6 membered monocyclic heteroaryl; R² is C₁-C₆ alkyl; R³ is G^(3A); and G^(3A) is an optionally substituted 4-7 membered monocyclic heterocycle.
 16. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R¹ is G^(1A); G^(1A) is optionally substituted phenyl or optionally substituted 5-6 membered monocyclic heteroaryl; R² is G^(2A); G^(2A) is optionally substituted C₃-C₆ monocyclic cycloalkyl; R³ is G^(3A); and G^(3A) is optionally substituted phenyl, optionally substituted 5-6 membered monocyclic heteroaryl, or optionally substituted 4-11 membered heterocycle.
 17. The compound of claim 16 or a pharmaceutically acceptable salt thereof, wherein G^(3A) is an optionally substituted 4-7 membered monocyclic heterocycle.
 18. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R¹ is G^(1A); G^(1A) is optionally substituted phenyl or optionally substituted 5-6 membered monocyclic heteroaryl; R² is C₁-C₆ alkyl or G^(2A); G^(2A) is optionally substituted C₃-C₆ monocyclic cycloalkyl; and R³ is -G^(3B)-L¹-G^(3C).
 19. The compound of claim 18 or a pharmaceutically acceptable salt thereof, wherein L¹ is a bond, C₁-C₃ alkylenyl, or (C₁-C₃ alkylenyl)_(r)-L²-(C₁-C₃ alkylenyl)_(s); L² is O, N(R^(x)), or C(O); and G^(3B) is optionally substituted phenyl, optionally substituted 5-6 membered monocyclic heteroaryl, or optionally substituted 4-7 membered monocyclic heterocycle.
 20. The compound of claim 19 or a pharmaceutically acceptable salt thereof, wherein L² is O or N(R^(x)); and G^(3B) is an optionally substituted 4-7 membered monocyclic heterocycle.
 21. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R¹ is G^(1A); G^(1A) is optionally substituted phenyl or optionally substituted 5-6 membered monocyclic heteroaryl; R² is C₁-C₆ alkyl or G^(2A); G^(2A) is optionally substituted C₃-C₆ monocyclic cycloalkyl; R³ is —OR^(3a); and R^(3a) is G^(3E), C₁-C₆ haloalkyl, or C₁-C₆ alkyl; wherein the C₁-C₆ haloalkyl and the C₁-C₆ alkyl are each substituted with one or two substituents independently selected from the group consisting of G^(3E), —OR^(3xa), —C(O)G^(3D), —N(R^(3xb))₂, and —S(O)₂R^(3xc).
 22. The compound of claim 21 or a pharmaceutically acceptable salt thereof, wherein R^(3a) is C₁-C₆ haloalkyl or C₁-C₆ alkyl; wherein the C₁-C₆ haloalkyl and the C₁-C₆ alkyl are each substituted with one G^(3E).
 23. The compound of claim 22 or a pharmaceutically acceptable salt thereof, wherein G^(3E) is an optionally substituted 4-7 membered monocyclic heterocycle.
 24. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R¹ is -G^(1B)-G^(1C); R² is C₁-C₆ alkyl or G^(2A); and R³ is G^(3A), -G^(3B)-L¹-G^(3C), or —OR^(3a).
 25. The compound of claim 24 or a pharmaceutically acceptable salt thereof, wherein R³ is G^(3A); and G^(3A) is optionally substituted phenyl, optionally substituted 5-6 membered monocyclic heteroaryl, or optionally substituted 4-11 membered heterocycle.
 26. The compound of claim 24 or a pharmaceutically acceptable salt thereof, wherein R³ is G^(3A); and G^(3A) is optionally substituted 4-7 membered monocyclic heterocycle.
 27. The compound of claim 24 or a pharmaceutically acceptable salt thereof, wherein R³ is -G^(3B)-L¹-G^(3C); and G^(3B) is optionally substituted phenyl, optionally substituted 5-6 membered monocyclic heteroaryl, or optionally substituted 4-7 membered monocyclic heterocycle.
 28. The compound of claim 24 or a pharmaceutically acceptable salt thereof, wherein R³ is -G^(3B)-L¹-G^(3C); L¹ is a bond, C₁-C₃ alkylenyl, or (C₁-C₃ alkylenyl)_(r)-L²-(C₁-C₃ alkylenyl)_(s); L² is O or N(R^(x)); and G^(3B) is optionally substituted 4-7 membered monocyclic heterocycle.
 29. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R³ is -G^(3B)-L³-G^(3C)-L⁴-G^(3F) or —(C₁-C₆ alkylenyl)-G^(3E).
 30. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R¹ is G^(1A) or -G^(1B)-G^(1C); R² is C₁-C₆ alkyl or G^(2A); and R³ is -G^(3B)-L³-G^(3C)-L⁴-G^(3F) or —(C₁-C₆ alkylenyl)-G^(3E).
 31. The compound of claim 30 or a pharmaceutically acceptable salt thereof, wherein R¹ is G^(1A); G^(1A) is optionally substituted phenyl or optionally substituted 5-6 membered monocyclic heteroaryl; G^(2A) is optionally substituted C₃-C₆ monocyclic cycloalkyl; and L⁴ is a bond, —(C₁-C₆ alkylenyl), N(R^(2x)), or C(O).
 32. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein the compound is selected from the group consisting of: 3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-(4-methoxyphenyl)-3-methyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclopentyl-4-(4-methoxyphenyl)-3-methyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(2-cyanoethyl)-4-(4-methoxyphenyl)-3-methyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(morpholin-4-yl)phenyl]-1-phenyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-[5-(trifluoromethyl)-1H-pyrazol-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-1-phenyl-4-[4-(piperidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[4-(4-methylpiperazin-1-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3,5-difluorophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-chlorophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-fluorophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-1-(3-methylphenyl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(1,1-dioxo-1λ⁶,4-thiazinan-4-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[2-(morpholin-4-yl)pyrimidin-5-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-(ethoxycarbonyl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-bromophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-(hydroxymethyl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-methylphenyl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-methoxyphenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-(oxan-4-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-phenyl-3-(propan-2-yl)-4-[4-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-1-phenyl-4-[4-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[2-chloro-4-(morpholin-4-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[4-(1-methyl-1,2,3,6-tetrahydropyridin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(3-fluoropyrrolidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-acetylpiperazin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3,5-dimethylphenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-[4-(trifluoromethoxy)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-1-[3-(morpholin-4-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[2-methoxy-4-(morpholin-4-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclopropyl-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-[3-(trifluoromethoxy)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(dimethylamino)phenyl]-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3,4-difluorophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(methanesulfonyl)phenyl]-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-1-(1-methylpiperidin-4-yl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-tert-butyl-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(2-chloropyridin-4-yl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3,5-dimethyl-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1-[4-(trifluoromethoxy)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3,5-dichlorophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-(3-sulfamoylphenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-1-(1-methyl-1H-pyrazol-4-yl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-[1-(tert-butoxycarbonyl)azetidin-3-yl]-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(morpholin-4-yl)phenyl]-1-phenyl-3-(prop-1-en-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-cyanophenyl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(2-methoxypyridin-4-yl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-fluoro-5-methoxyphenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[4-(methanesulfonyl)piperazin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-(methylcarbamoyl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-(1-hydroxy-2-methylpropan-2-yl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(2-fluoropyridin-4-yl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[4-(morpholin-4-yl)phenyl]-1-(2-oxo-1,2-dihydropyridin-4-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-carbamoylphenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-tert-butylpiperazin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(6-methoxypyridin-3-yl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[2-(dimethylamino)pyrimidin-5-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-(2-hydroxypropan-2-yl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-carbamoyl-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-3-methyl-4-[2-(morpholin-4-yl)pyrimidin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[3-bromo-4-(morpholin-4-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclopentyl-4-[2-(dimethylamino)pyrimidin-5-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(morpholin-4-yl)phenyl]-1-(oxan-3-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclopentyl-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[4-(methoxycarbonyl)piperazin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(1-acetylpiperidin-4-yl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[3-(dimethylamino)azetidin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(3,3-dimethylazetidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-3-methyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[2-(dimethylamino)pyrimidin-5-yl]-3-methyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-[1-(tert-butoxycarbonyl)pyrrolidin-2-yl]-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclopentyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-(1-acetylazetidin-3-yl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[2-(morpholin-4-yl)pyrimidin-5-yl]-1-phenyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[2-(morpholin-4-yl)pyrimidin-5-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-1-phenyl-4-{4-[4-(3,3,3-trifluoropropyl)piperazin-1-yl]phenyl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclopentyl-4-[6-(dimethylamino)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(dimethylamino)phenyl]-4-[2-(morpholin-4-yl)pyrimidin-5-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(dimethylamino)phenyl]-4-[6-(morpholin-4-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-[1-(methoxycarbonyl)azetidin-3-yl]-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-[(dimethylamino)methyl]-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[2-(dimethylamino)pyrimidin-5-yl]-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(dimethylamino)pyridin-3-yl]-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(dimethylamino)phenyl]-3-methyl-4-[2-(morpholin-4-yl)pyrimidin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-tert-butyl-1-cyclopentyl-4-[2-(dimethylamino)pyrimidin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-(1-hydroxy-2-methylpropan-2-yl)-4-[6-(morpholin-4-yl)pyridin-3-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[6-(dimethylamino)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-1-(1-methyl-2-oxo-1,2-dihydropyridin-4-yl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[1-(cyanomethyl)piperidin-4-yl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(cyclobutylamino)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(3,3-difluoroazetidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[4-(cyanomethyl)piperazin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[6-(dimethylamino)pyridin-3-yl]-3-methyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-tert-butyl-1-cyclopentyl-4-[2-(morpholin-4-yl)pyrimidin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-fluorophenyl)-3-methyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-[1-(tert-butoxycarbonyl)pyrrolidin-2-yl]-4-[6-(morpholin-4-yl)pyridin-3-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(2,4-difluorophenyl)-3-methyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(2,4-difluorophenyl)-3-methyl-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclopentyl-3-methyl-4-[6-(morpholin-4-yl)pyridin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[4-(2-hydroxyethyl)piperazin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4,4-difluoropiperidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-cyanopiperidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-{4-[methyl(oxan-4-yl)amino]phenyl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(3,3-difluoropyrrolidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-{4-[(oxetan-3-yl)amino]phenyl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-(3-methyloxetan-3-yl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(2,6-dimethylmorpholin-4-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[cyclobutyl(methyl)amino]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[(3R,4R)-3,4-dihydroxypyrrolidin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1-[1-(2,2,2-trifluoroethyl)piperidin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-(morpholin-4-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(2,2-dimethylmorpholin-4-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(morpholin-4-yl)phenyl]-1-(oxolan-3-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(morpholin-4-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-(methoxymethyl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-1-phenyl-4-(piperidin-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(3-hydroxyazetidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(3-fluoroazetidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[4-(2-oxa-6-azaspiro[3.3]heptan-6-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-{4-[(1S,4S)-2-oxa-5-azabicyclo[2.2.1]heptan-5-yl]phenyl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(3,6-dihydro-2H-pyran-4-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-(1-methylcyclopropyl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-tert-butyl-1-cyclohexyl-4-[4-(dimethylamino)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-acetylpiperazin-1-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[2-(hydroxymethyl)morpholin-4-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[4-(8-oxa-3-azabicyclo[3.2.1]octan-3-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(azetidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(cyanomethyl)piperazin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-hydroxypiperidin-1-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(1-acetylpiperidin-4-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[1-(cyanomethyl)piperidin-4-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-{4-[methyl(oxetan-3-yl)amino]phenyl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[1-(cyanomethyl)pyrrolidin-3-yl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[1-(methoxycarbonyl)pyrrolidin-3-yl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-methoxypiperidin-1-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-hydroxypiperidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-{4-[(oxan-4-yl)amino]phenyl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(methanesulfonyl)piperazin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-tert-butyl-1-cyclohexyl-4-[2-(dimethylamino)pyrimidin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-[1-(cyanomethyl)azetidin-3-yl]-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-tert-butyl-1-cyclohexyl-4-[2-(morpholin-4-yl)pyrimidin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-(2-oxopiperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(azetidin-1-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(cyclohexylmethoxy)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(3-hydroxypyrrolidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[4-(2-oxa-7-azaspiro[3.5]nonan-7-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[(3S)-3-cyanopyrrolidin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(3-acetamidopyrrolidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-1-phenyl-4-(piperidine-1-carbonyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4,4-difluorocyclohexyl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(3,3-dimethylazetidin-1-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1-[1-(2,2,2-trifluoroethyl)piperidin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-methylphenyl)-4-(piperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[(1R,3R)-3-(benzyloxy)cyclohexyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(3-methoxyazetidin-1-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(3-fluoropyrrolidin-1-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[2-(dimethylamino)pyrimidin-5-yl]-3-[1-(methoxycarbonyl)azetidin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(3-fluoroazetidin-1-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-{6-[(2-methoxyethyl)(methyl)amino]pyridin-3-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-acetamidophenyl)-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-{3-[(2-methoxyethyl)(methyl)amino]phenyl}-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-methylphenyl)-3-(propan-2-yl)-4-(pyrrolidin-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(3-fluoroazetidin-1-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-cyanopiperidin-1-yl)phenyl]-1-[3-(dimethylamino)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-[3-(dimethylamino)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{6-[(2-methoxyethyl)(methyl)amino]pyridin-3-yl}-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[6-(3,3-difluoropyrrolidin-1-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-{4-[(2-methoxyethyl)(methyl)amino]phenyl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-cyanopiperidin-1-yl)phenyl]-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(morpholin-4-yl)phenyl]-3-(oxolan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[(2-methoxyethyl)(methyl)amino]phenyl}-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(dimethylamino)phenyl]-4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(3-methoxypiperidin-1-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-cyanopiperidin-1-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-methoxypiperidin-1-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-3-cyclopropyl-4-[6-(dimethylamino)pyridin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; rac-1-[(1R,3R)-3-hydroxycyclohexyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; rac-1-[(1R,3S)-3-hydroxycyclohexyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[6-(2,6-dimethylmorpholin-4-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[6-(2,2-dimethylmorpholin-4-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(3-hydroxypiperidin-1-yl)phenyl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[2-(4-cyanopiperidin-1-yl)pyrimidin-5-yl]-1-[3-(dimethylamino)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(dimethylamino)phenyl]-4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(morpholin-4-yl)phenyl]-1-[2-(morpholin-4-yl)pyridin-4-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-methylphenyl)-4-(2-oxa-7-azaspiro[3.5]nonan-7-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyano-4-methylpiperidin-1-yl)pyridin-3-yl]-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[2-(4-cyanopiperidin-1-yl)pyrimidin-5-yl]-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[(1R,3S)-3-methoxycyclohexyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-cyanopiperidin-1-yl)phenyl]-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(dimethylamino)phenyl]-4-{4-[methyl(oxan-4-yl)amino]phenyl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[methyl(oxan-4-yl)amino]phenyl}-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(2-methoxyethyl)(methyl)amino]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4,4-difluoropiperidin-1-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(morpholin-4-yl)phenyl]-1-[5-(morpholin-4-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(3-methoxyazetidin-1-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(hydroxymethyl)piperidin-1-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[(1R,3R)-3-methoxycyclohexyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-methylphenyl)-3-(propan-2-yl)-4-[3-(trifluoromethyl)pyrrolidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[5-(tert-butoxycarbonyl)hexahydropyrrolo[3,4-c]pyrrol-2(1H)-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[3-(dimethylamino)pyrrolidin-1-yl]phenyl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(3-cyanopyrrolidin-1-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-cyanopiperidin-1-yl)phenyl]-3-cyclobutyl-1-cyclohexyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-cyclobutyl-1-cyclohexyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-cyanopiperidin-1-yl)phenyl]-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[6-(3-fluoropiperidin-1-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[6-(3-methoxypyrrolidin-1-yl)pyridin-3-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(3-hydroxyazetidin-1-yl)phenyl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[5-(cyanomethyl)hexahydropyrrolo[3,4-c]pyrrol-2(1H)-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(methoxymethyl)piperidin-1-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(2-methoxyethyl)piperidin-1-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-chloropyridin-2-yl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{2-[(2-methoxyethyl)(methyl)amino]pyrimidin-5-yl}-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-1-[3-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[4-(cyanomethyl)piperazin-1-yl]phenyl}-1-(3-methoxyphenyl)-3-methyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(5-acetylhexahydropyrrolo[3,4-c]pyrrol-2(1H)-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[1-(tert-butoxycarbonyl)octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[2-(4-cyanopiperidin-1-yl)pyrimidin-5-yl]-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-{2-[(2-methoxyethyl)(methyl)amino]pyrimidin-5-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[(2-methoxyethyl)(methyl)amino]phenyl}-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(azetidin-1-yl)phenyl]-4-{6-[(2-methoxyethyl)(methyl)amino]pyridin-3-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(azetidin-1-yl)phenyl]-4-{4-[methyl(oxan-4-yl)amino]phenyl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(morpholin-4-yl)phenyl]-1-[4-(morpholin-4-yl)pyridin-2-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-fluorophenyl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3,4-difluorophenyl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(morpholin-4-yl)phenyl]-1-[6-(morpholin-4-yl)pyridin-2-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3,5-difluorophenyl)-4-{4-[methyl(oxan-4-yl)amino]phenyl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3,5-difluorophenyl)-4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-cyanopiperidin-1-yl)phenyl]-3-cyclobutyl-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-cyclobutyl-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[methyl(oxan-4-yl)amino]phenyl}-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[methyl(oxan-4-yl)amino]phenyl}-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{6-[(2-methoxyethyl)(methyl)amino]pyridin-3-yl}-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-{4-[methyl(oxan-4-yl)amino]phenyl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(1-acetyloctahydro-5H-pyrrolo[3,2-c]pyridin-5-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[1-(cyanomethyl)octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(methanesulfonyl)piperidin-1-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-methylphenyl)-4-(7-oxa-2-azaspiro[3.5]nonan-2-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[2-(4-cyanopiperidin-1-yl)pyrimidin-5-yl]-3-(propan-2-yl)-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(propan-2-yl)-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-cyanopiperidin-1-yl)phenyl]-3-(propan-2-yl)-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-methylphenyl)-4-(8-oxa-2-azaspiro[4.5]decan-2-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-cyanopiperidin-1-yl)-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-(4-methoxypiperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-(piperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[4-(hydroxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[6-(dimethylamino)pyridin-2-yl]-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3,5-difluorophenyl)-4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(morpholin-4-yl)phenyl]-3-(propan-2-yl)-1-[3-(trifluoromethoxy)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(dimethylamino)phenyl]-3-(propan-2-yl)-4-[3-(trifluoromethyl)pyrrolidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(1,1-difluoro-5-azaspiro[2.4]heptan-5-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[3-(methanesulfonyl)pyrrolidin-1-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(2-azaspiro[3.3]heptan-2-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-methylphenyl)-4-(5-oxa-2-azaspiro[3.5]nonan-2-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{6-[bis(2-methoxyethyl)amino]pyridin-3-yl}-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-{6-[methyl(oxolan-3-yl)amino]pyridin-3-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-1-[3-(pyrrolidin-1-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3,4-difluorophenyl)-4-{4-[methyl(oxan-4-yl)amino]phenyl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-(3,4-difluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-3-(propan-2-yl)-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-cyanopiperidin-1-yl)phenyl]-1-(3,5-difluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-fluorophenyl)-4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-fluorophenyl)-4-{4-[methyl(oxan-4-yl)amino]phenyl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-(3-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-cyanopiperidin-1-yl)phenyl]-1-(3-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{6-[methyl(oxan-4-yl)amino]pyridin-3-yl}-3-(propan-2-yl)-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-(4-methyl-3-oxo-1-oxa-4,9-diazaspiro[5.5]undecan-9-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[3-(methoxymethyl)-3-methylazetidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-(3-oxohexahydroimidazo[1,5-a]pyrazin-2(3H)-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(methoxymethyl)piperidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-acetamidopiperidin-1-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-(7-oxa-2-azaspiro[3.5]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[3-(methoxymethyl)azetidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3R)-3-methoxypyrrolidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3S)-3-methoxypyrrolidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-fluoropiperidin-1-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3R)-3-fluoropyrrolidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(3,3-difluoropyrrolidin-1-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3S)-3-fluoropyrrolidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-(3-oxotetrahydro-3H-[1,3]oxazolo[3,4-a]pyrazin-7(1H)-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[3-(morpholin-4-yl)azetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[(methanesulfonyl)amino]piperidin-1-yl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(3-azabicyclo[3.1.0]hexan-3-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-1-phenyl-4-[4-(pyrrolidine-1-carbonyl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-(6-oxa-2-azaspiro[3.4]octan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(2-azaspiro[3.4]octan-2-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-(6-oxa-2-azaspiro[3.5]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(2-azaspiro[3.5]nonan-2-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(5-azaspiro[2.5]octan-5-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-(1-oxa-7-azaspiro[4.4]nonan-7-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-(5-oxa-2-azaspiro[3.5]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-(6-oxo-2,7-diazaspiro[4.4]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[(1S)-2-(dimethylamino)-1-fluoroethyl]piperidin-1-yl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-(1,4-oxazepan-4-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3-fluorophenyl)-4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(3,5-difluorophenyl)-4-{2-[methyl(oxan-4-yl)amino]pyrimidin-5-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(2-methoxyethoxy)piperidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(dimethylcarbamoyl)piperidin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(methanesulfonyl)-1,4-diazepan-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(3-methoxypropyl)piperazin-1-yl]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[4-(morpholine-4-carbonyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[2-(dimethylamino)-2-oxoethyl]piperazin-1-yl}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[2-(4-cyanopiperidin-1-yl)pyrimidin-5-yl]-1-(2,4-difluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-(2,4-difluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-cyanopiperidin-1-yl)phenyl]-1-(2,4-difluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(dimethylamino)phenyl]-4-(piperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-cyanopiperidin-1-yl)-1-[3-(dimethylamino)phenyl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(dimethylamino)phenyl]-4-(4-methoxypiperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(dimethylamino)phenyl]-4-[4-(hydroxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-(1-methylcyclobutyl)-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{[cis-3-(1,1-dioxo-1λ⁶,4-thiazinan-4-yl)cyclobutyl]oxy}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[2-(1,1-dioxo-1λ⁶,4-thiazinan-4-yl)ethoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(2S)-2-fluoro-2-(oxan-4-yl)ethoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(2R)-2-fluoro-2-(oxan-4-yl)ethoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-{[(3S)-1-methylpyrrolidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-{[(3R)-1-methylpyrrolidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[(1-methylpiperidin-4-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{[cis-3-(dimethylamino)cyclobutyl]oxy}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[(oxetan-3-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-1-phenyl-4-[2-(pyrrolidin-1-yl)ethoxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-{[(3R)-1-methylpiperidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[(2-oxaspiro[3.3]heptan-6-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-1-phenyl-4-{[trans-3-(piperidin-1-yl)cyclobutyl]oxy}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-1-phenyl-4-{[cis-3-(piperidin-1-yl)cyclobutyl]oxy}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[2-(3,3-difluorocyclobutyl)ethoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(fluoromethyl)piperidin-1-yl]-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(3-fluorophenyl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(3,4-difluorophenyl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-(1-methyl-1H-pyrrol-3-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-(1,3-dimethyl-1H-pyrazol-4-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(3,5-difluorophenyl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(morpholin-4-yl)phenyl]-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(3-fluoro-4-methylphenyl)-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(morpholin-4-yl)phenyl]-1-[4-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-[4-(dimethylamino)phenyl]-4-[4-(morpholin-4-yl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-methoxypiperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(3-methyl-2-oxo-1-oxa-3,8-diazaspiro[4.5]decan-8-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(3-azaspiro[5.5]undecan-3-yl)-1-(3-methylphenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-3-(propan-2-yl)-4-[1-(propan-2-yl)-1H-pyrazol-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-(1-methyl-1H-pyrrol-2-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-3-(propan-2-yl)-4-(1H-pyrazol-4-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-(1-oxo-2,3-dihydro-1H-isoindol-5-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-(oxan-3-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[2-(3-cyanopiperidin-1-yl)pyrimidin-5-yl]-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[2-oxo-2-(pyrrolidin-1-yl)ethoxy]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(dimethylamino)phenyl]-4-[4-(methoxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(propan-2-yl)-1-[2-(pyrrolidin-1-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-(1-methyl-1H-pyrazol-5-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[1-(tert-butoxycarbonyl)-1,2,3,6-tetrahydropyridin-4-yl]-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-{4-[(propan-2-yl)oxy]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(methoxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(2-{[1-(tert-butoxycarbonyl)piperidin-4-yl](methyl)amino}pyrimidin-5-yl)-1-cyclohexyl-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[(3-methyloxetan-3-yl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(4-methoxycyclohexyl)oxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[2-fluoro-2-(oxan-4-yl)ethoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3-fluoro-1-methylpyrrolidin-3-yl)methoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(2S)-2-fluoro-2-(1-methylpiperidin-4-yl)ethoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(2R)-2-fluoro-2-(1-methylpiperidin-4-yl)ethoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[3-fluoro-1-(oxetan-3-yl)piperidin-3-yl]methoxy-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3,3-difluorocyclopentyl)methoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-methyl-4-[2-oxo-2-(piperidin-1-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[1-(methanesulfonyl)cyclobutyl]methoxy-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{2-[cyclopropyl(2-methylpropyl)amino]ethoxy}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3,3-difluoro-1-methylcyclobutyl)methoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{[1-(fluoromethyl)cyclopropyl]methoxy}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{[1-(2-methoxyethyl)cyclopropyl]methoxy}-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(2,2-difluorocyclopentyl)methoxy]-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(morpholin-4-yl)phenyl]-1-phenyl-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[4-(methoxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-cyanopiperidin-1-yl)phenyl]-3-(propan-2-yl)-1-[2-(pyrrolidin-1-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-(4-methoxypiperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[4-(hydroxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-butoxypiperidin-1-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[4-(2-methylpropoxy)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-(4-methoxy-4-methylpiperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-(1-oxa-7-azaspiro[3.5]nonan-7-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[3-(difluoromethyl)piperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-(6-oxa-2-azaspiro[3.5]nonan-2-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-(1-oxa-8-azaspiro[4.5]decan-8-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-3-(propan-2-yl)-4-(2,2,6,6-tetramethyl-3,6-dihydro-2H-pyran-4-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(2-methoxyethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(2-azaspiro[3.4]octan-2-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(methoxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(3-azabicyclo[3.1.0]hexan-3-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(cyclohexylmethoxy)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-(piperidin-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(2-azaspiro[3.5]nonan-2-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-cyanopiperidin-1-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(methanesulfonyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-methoxypiperidin-1-yl)-3-(propan-2-yl)-1-[2-(pyrrolidin-1-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-cyclobutyl-1-[2-(pyrrolidin-1-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[2-(oxan-4-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(2S)-2-fluoro-2-(oxan-4-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-cyclobutyl-1-[2-(morpholin-4-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(oxan-4-yl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(methoxymethyl)azetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(5-azaspiro[2.5]octan-5-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(3,3-difluorocyclobutyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(cis-3-methoxycyclobutyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(2-methoxyethyl)(methyl)amino]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(1,1-difluoro-5-azaspiro[2.4]heptan-5-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(5-oxa-2-azaspiro[3.5]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(7-oxa-2-azaspiro[3.5]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(2-azaspiro[3.3]heptan-2-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[(benzyloxy)methyl]piperidin-1-yl}-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(cis-4-methoxycyclohexyl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(trans-4-methoxycyclohexyl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(3,3-dimethylcyclobutyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[4-(methoxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(cis-3-fluorocyclobutyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(trans-3-fluorocyclobutyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(2R)-2-fluoro-2-(oxan-4-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3,3-difluorocyclopentyl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[2-(1,1-dioxo-1λ⁶,4-thiazinan-4-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-[2-(morpholin-4-yl)pyridin-4-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[4-(2-methoxypropan-2-yl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(cis-3-tert-butoxycyclobutyl)(methyl)amino]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(3-methylazetidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(3,3-difluoropyrrolidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-[3-(trifluoromethyl)pyrrolidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-[4-(pyrrolidin-1-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-fluoropiperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3R,4R)-3,4-dihydroxypyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3S,4S)-3,4-dihydroxypyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[2-(dimethylamino)ethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[2-(diethylamino)ethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(cyclopropylmethyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-cyclobutylpiperazin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(3-fluoro-3-methylazetidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(8-azaspiro[4.5]decan-8-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(3,3-difluoro-1-oxa-8-azaspiro[4.5]decan-8-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(1′-methyl[4,4′-bipiperidin]-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(1R)-2-(dimethylamino)-1-fluoroethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(1S)-2-(dimethylamino)-1-fluoroethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(1S)-1-fluoro-2-hydroxyethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(1R)-1-fluoro-2-hydroxyethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-fluoro-4-[(2-methoxyethoxy)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(ethoxymethyl)-3-fluoropiperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(ethoxymethyl)-4-fluoropiperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{3-fluoro-3-[(2-methoxyethoxy)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-fluoro-4-(methoxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3R,4R)-3-fluoro-4-hydroxypiperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3R,4R)-4-fluoro-3-hydroxypiperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-[3-(piperidin-1-yl)azetidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3R)-3-(methanesulfonyl)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(3-methoxypiperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-oxo-1-(propan-2-yl)-1,3,8-triazaspiro[4.5]decan-8-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-[4-(2,2,2-trifluoroethyl)piperazin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(3-hydroxypropyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[2-oxo-2-(pyrrolidin-1-yl)ethyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(azepan-1-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[2-(morpholin-4-yl)-2-oxoethyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(7R,8aS)-7-hydroxyhexahydropyrrolo[1,2-a]pyrazin-2(1H)-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3,3-difluoro-1-methylcyclobutyl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[2-(3,3-difluorocyclobutyl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{2-[(oxetan-3-yl)(propan-2-yl)amino]ethoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(1-acetyl-4-fluoropiperidin-4-yl)methoxy]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[(2S)-oxolan-2-yl]methoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[2-(3-methoxyazetidin-1-yl)-2-oxoethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(2R)-2-fluoro-2-(1-methylpiperidin-4-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{2-[(oxetan-3-yl)oxy]ethoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{2-[1-(2-methoxyethyl)cyclopropyl]ethoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[1-(2-methoxyethyl)cyclopropyl]methoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(2,2-difluorocyclopentyl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(morpholin-4-yl)propoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[2-(1,3-dioxan-2-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(3-fluoropropoxy)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3-methyloxetan-3-yl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(1,3-dimethoxypropan-2-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[cis-3-(dimethylamino)cyclobutyl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(2-methyl-1,3-dioxan-5-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[(3S)-1-methylpiperidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(2-oxaspiro[3.3]heptan-6-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[(3R)-1-methylpiperidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-[(1-acetylazetidin-3-yl)oxy]-4-[4-(morpholin-4-yl)phenyl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(1-methoxyethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-[4-(1,1,1-trifluoro-2-methoxypropan-2-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(diethylcarbamoyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-hydroxypiperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[2-(1,4-dimethyl-6-oxo-1,6-dihydropyrimidin-5-yl)ethyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(4aS,7aR)-4-methyl-3-oxohexahydropyrrolo[3,4-b][1,4]oxazin-6(2H)-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(3-oxopiperazin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(5 aS,8aS)-2-oxooctahydropyrrolo[3,4-b]azepin-7(1H)-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(2R)-4,4-difluoro-2-(hydroxymethyl)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(2S,4S)-4-fluoro-2-(hydroxymethyl)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-fluoro-3-(methoxymethyl)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3R,4S)-3-fluoro-4-hydroxypiperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(ethoxymethyl)-3-fluoropyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(hydroxymethyl)-3-methylazetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3S)-3-methoxypyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(2,2-difluoroethoxy)azetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(2R,4S)-4-fluoro-2-(hydroxymethyl)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(7S,8aS)-7-fluorohexahydropyrrolo[1,2-a]pyrazin-2(1H)-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(4aS,7aS)-4-methyl-3-oxohexahydropyrrolo[3,4-b][1,4]oxazin-6(2H)-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-fluoro-4-(hydroxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(1-oxa-7-azaspiro[4.4]nonan-7-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(methanesulfonyl)amino]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(1-fluoro-2-hydroxyethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(methoxymethyl)-3-methylazetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3R)-3-methoxypyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(methanesulfonyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{6-[bis(2-methoxyethyl)amino]pyridin-3-yl}-1-[2-(morpholin-4-yl)pyridin-4-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(methoxymethyl)piperidin-1-yl]-1-[2-(morpholin-4-yl)pyridin-4-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-methoxy-4-(methoxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3S)-3-fluoropyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(3,3-difluoroazetidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(2-oxo-1,3-oxazolidin-3-yl)azetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(3-ethyl-3-fluoroazetidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[2-(hydroxymethyl)morpholin-4-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{3-fluoro-3-[(2-methoxyethoxy)methyl]pyrrolidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(cis-3-hydroxycyclobutyl)(methyl)amino]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(6-oxa-2-azaspiro[3.4]octan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3R,4S)-4-fluoro-3-hydroxypiperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(3-hydroxy-3-methylazetidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(6-oxo-2,7-diazaspiro[4.4]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(2S)-4,4-difluoro-2-(hydroxymethyl)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(ethoxycarbonyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[2-(cyclohexylamino)-2-oxoethyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3R)-3-fluoropyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(3-methoxyazetidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(2-hydroxy-7-azaspiro[3.5]nonan-7-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3R)-3-(hydroxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(1,4-oxazepan-4-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-hydroxy-4-(2-hydroxyethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(cyclobutylmethyl)-4-[4-(methoxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(methoxymethyl)piperidin-1-yl]-1-(2-methylpropyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; rac-4-[(3aR,7aS)-1-(tert-butoxycarbonyl)octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-phenyl-3-[(pyrrolidin-3-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-(trans-3-methylcyclobutyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-{[1-(tert-butoxycarbonyl)pyrrolidin-3-yl]oxy}-4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-{[1-(tert-butoxycarbonyl)piperidin-4-yl]oxy}-4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{methyl[(oxan-4-yl)methyl]amino}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-[4-(2-propoxyethyl)piperazin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-{2-[(piperidin-1-yl)methyl]morpholin-4-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-{4-[(pyrrolidin-1-yl)methyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[3-(morpholin-4-yl)propyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[2-(dimethylamino)-2-oxoethyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(2-cyanoethyl)piperazin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{2-[(dimethylamino)methyl]morpholin-4-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-methylpiperazin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(methyl {[1-(2-methylpropyl)piperidin-4-yl]methyl}amino)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{methyl[2-(morpholin-4-yl)ethyl]amino}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(2-ethoxyethyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3R)-3-(dimethylamino)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3S)-3-(dimethylamino)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[2-(methylamino)-2-oxoethyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(morpholin-4-yl)acetyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(2-methoxyethyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(oxolan-2-yl)methyl]-1,4-diazepan-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-{3-[(propan-2-yl)oxy]azetidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-{4-[2-(pyrrolidin-1-yl)ethyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[2-(morpholin-4-yl)ethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-([1,4′-bipiperidin]-1′-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3R)-3-(morpholin-4-yl)pyrrolidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(4,4-difluorocyclohexyl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(oxan-4-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[(1S,2S)-2-methoxycyclohexyl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3-ethyloxetan-3-yl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[(3R)-oxolan-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[(3S)-oxolan-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-methoxy-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(cyclobutyloxy)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[2-(2-methoxyethoxy)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3aR,7aS)-1-acetyloctahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3aS,7aR)-1-acetyloctahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(methoxymethyl)piperidin-1-yl]-1-[2-(morpholin-4-yl)pyrimidin-4-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[(oxan-4-yl)methyl]amino}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-[(oxolan-3-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[6-(4-cyanopiperidin-1-yl)pyridin-3-yl]-3-[(oxetan-3-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{methyl[(1-methylpiperidin-3-yl)methyl]amino}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4,4-difluoropiperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-fluoro-3-(methoxymethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-[2-(trifluoromethyl)morpholin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(cyclopentyloxy)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{[cis-3-(azetidin-1-yl)cyclobutyl]oxy}-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(1-cyclohexylazetidin-3-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3,3-difluorocyclobutyl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(1-methylazetidin-3-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[3-(dimethylamino)phenyl]-4-[(oxan-4-yl)methoxy]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[(oxan-4-yl)methoxy]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[2-(oxan-4-yl)ethoxy]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(2-methoxypropan-2-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[3-(dimethylamino)propoxy]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[3-(morpholin-4-yl)propoxy]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[(3-methyloxetan-3-yl)methoxy]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[(oxolan-2-yl)methoxy]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; rac-3-cyclobutyl-1-phenyl-4-[(3aR,7aS)-1-{[(propan-2-yl)oxy]carbonyl}octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(dimethylamino)butoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(1-acetylpiperidin-4-yl)oxy]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-(2,2,2-trifluoroethoxy)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{2-[2-(dimethylamino)ethoxy]ethoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[(2S)-1-(dimethylamino)propan-2-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(4,4-difluorocyclohexyl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[(2R)-5-oxopyrrolidin-2-yl]methoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[(4R)-2,2-dimethyl-1,3-dioxolan-4-yl]methoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[(3S)-6-oxopiperidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(5-ethyl-1,3-dioxan-5-yl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[(3-endo)-8-methyl-8-azabicyclo[3.2.1]octan-3-yl]oxy}-1-phenyl-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(5-methyl-1,3-dioxan-5-yl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[2-(1,4-dioxa-8-azaspiro[4.5]decan-8-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(diethylamino)propoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{2-[cyclohexyl(oxetan-3-yl)amino]ethoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[4-fluoro-1-(methanesulfonyl)piperidin-4-yl]methoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[4-(methanesulfonyl)oxan-4-yl]methoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-[2-(pyrrolidin-1-yl)ethoxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[2-(methanesulfonyl)-2-methylpropoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(1-methylcyclopropyl)methoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[2-(1-methylcyclopropyl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[1-(methanesulfonyl)cyclobutyl]methoxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(2-cyclohexylethoxy)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(4-methylpiperazin-1-yl)propoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(dimethylamino)propoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(dimethylamino)-2,2-dimethylpropoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[2-(dimethylamino)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{[1,3-bis(dimethylamino)propan-2-yl]oxy}-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-[2-(piperidin-1-yl)ethoxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[2-(2-oxoimidazolidin-1-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{[1,3-bis(morpholin-4-yl)propan-2-yl]oxy}-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-[3-(piperidin-1-yl)propoxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[2-(azepan-1-yl)ethoxy]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[2-(4-methyl-1,4-diazepan-1-yl)ethoxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[(2s,4r)-5-methyl-5-azaspiro[3.4]octan-2-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(1-{3-[(diethylamino)methyl]oxetan-3-yl}azetidin-3-yl)oxy]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-{[1-(propan-2-yl)piperidin-4-yl]oxy}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(cycloheptyloxy)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(cyclooctyloxy)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[(3R)-1-methylpyrrolidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{[(3S)-1-methylpyrrolidin-3-yl]oxy}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3,3-difluoro-1-methylcyclobutyl)methoxy]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[3-(piperidin-1-yl)propoxy]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(1,3-dimethoxypropan-2-yl)oxy]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-({[(2S)-oxolan-2-yl]methyl}amino)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[4-(2-hydroxypropan-2-yl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[4-(methoxymethyl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[(oxan-4-yl)methoxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(2-hydroxypropan-2-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(dimethylamino)piperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-(1′-methyl[4,4′-bipiperidin]-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(1-acetylpiperidin-4-yl)methoxy]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{[1-(methoxycarbonyl)piperidin-4-yl]methoxy}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[(oxane-4-carbonyl)amino]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(cyanomethyl)-4-hydroxypiperidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(ethoxymethyl)-4-fluoropiperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-fluoro-4-[(2-methoxyethoxy)methyl]piperidin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3R,4R)-3-fluoro-4-hydroxypiperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-fluoro-4-(methoxymethyl)piperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{3-fluoro-3-[(2-methoxyethoxy)methyl]piperidin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3S)-3-{[(tert-butoxycarbonyl)amino]methyl}pyrrolidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3R)-3-{[(tert-butoxycarbonyl)amino]methyl}pyrrolidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(1,1-dioxo-1λ⁶,4-thiazinan-4-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3R)-3-{[(tert-butoxycarbonyl)(methyl)amino]methyl}pyrrolidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3S)-3-{[(tert-butoxycarbonyl)(methyl)amino]methyl}pyrrolidin-1-yl]-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{(3S)-3-[(methylamino)methyl]pyrrolidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(2,6-dimethylpyridin-4-yl)-4-[4-(methoxymethyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(methoxymethyl)piperidin-1-yl]-1-(2-methoxypyridin-4-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-[3-(pyrrolidin-1-yl)azetidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(oxolan-2-yl)methyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(1-methoxypropan-2-yl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[1-(morpholin-4-yl)ethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(1,3-dioxolan-2-yl)methyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(2-methoxyethoxy)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-{4-[(piperidin-1-yl)methyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[2-(4-methylpiperidin-1-yl)ethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(2,6-dimethylmorpholin-4-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(diethylamino)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[{3-[cyclohexyl(methyl)amino]propyl}(methyl)amino]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-[4-(propan-2-yl)-1,4-diazepan-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3aR,6aS)-5-(2-methylpropyl)hexahydropyrrolo[3,4-c]pyrrol-2(1H)-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-([1,4′-bipiperidin]-1′-yl)-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[4-(2-methoxyethyl)piperazin-1-yl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[2-(4-methylpiperazin-1-yl)ethyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(ethoxyacetyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3R)-3-(2-oxopyrrolidin-1-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4′-methyl[1,4′-bipiperidin]-1′-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(9-methyl-3,9-diazaspiro[5.5]undecan-3-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(1,4-dioxa-8-azaspiro[4.5]decan-8-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(2-methylpropoxy)carbonyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-methyl-1,4-diazepan-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-acetylpiperazin-1-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(3-methoxypropyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-cyclopentyl-1,4-diazepan-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(3R)-3-hydroxypiperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-(4-propylpiperazin-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(dimethylcarbamoyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(morpholin-4-yl)azetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-butyl-1,4-diazepan-1-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(morpholine-4-carbonyl)[1,4′-bipiperidin]-1′-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-(4-propyl-1,4-diazepan-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(1,4-dioxa-7-azaspiro[4.4]nonan-7-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[2-(2-hydroxyethoxy)ethyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-[(3R)-3-(piperidin-1-yl)pyrrolidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(7-cyano-5-oxa-2-azaspiro[3.4]octan-2-yl)-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[3-(4-methyl-1,4-diazepan-1-yl)-3-oxopropyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(dimethylcarbamoyl)-4-(2-oxopyrrolidin-1-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(cyclohexylmethyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(6-oxa-2-azaspiro[3.5]nonan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[(8aR)-hexahydropyrrolo[1,2-a]pyrazin-2(1H)-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(2-hydroxyethyl)piperazin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[3-(4-methylmorpholin-2-yl)azetidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(3-{4-[methyl(oxetan-3-yl)amino]piperidin-1-yl}azetidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{3-[4-(morpholin-4-yl)piperidin-1-yl]azetidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[1-(2-ethoxyethyl)piperidin-4-yl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[1-(2-hydroxypropyl)piperidin-4-yl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[3-(dimethylamino)propyl]piperazin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[4-(2-ethoxyethyl)piperazin-1-yl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-{4-[2-(piperidin-1-yl)ethoxy]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[3-(diethylamino)propyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-{4-[3-(piperidin-1-yl)propyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-{4-[3-(pyrrolidin-1-yl)propyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[ethyl(oxetan-3-yl)amino]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[methyl(oxetan-3-yl)amino]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[1′-(oxetan-3-yl)[4,4′-bipiperidin]-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(dimethylamino)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(4-cyclopropylpiperazin-1-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(4-methylpiperazine-1-carbonyl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[3-(4-methylmorpholin-2-yl)azetidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[1-(2-ethoxyethyl)piperidin-4-yl]piperazin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{4-[1-(2-hydroxypropyl)piperidin-4-yl]piperazin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(1-cyclopropylpiperidin-4-yl)piperazin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{4-[4-(oxetan-3-yl)piperazin-1-yl]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[4-(2-ethoxyethyl)piperazin-1-yl]piperidin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{4-[4-(2-methoxyethyl)piperazin-1-yl]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[3-(diethylamino)propyl]piperidin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{4-[3-(piperidin-1-yl)propyl]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-3-(propan-2-yl)-4-{4-[3-(pyrrolidin-1-yl)propyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[ethyl(oxetan-3-yl)amino]piperidin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{4-[methyl(oxetan-3-yl)amino]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[1′-(oxetan-3-yl)[4,4′-bipiperidin]-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[4-(4-methylpiperazin-1-yl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(4-cyclopropylpiperazin-1-yl)piperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[4-(4-methylpiperazine-1-carbonyl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(4-methylpiperazin-1-yl)piperidin-1-yl]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-(3-{4-[methyl(oxetan-3-yl)amino]piperidin-1-yl}azetidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{3-[4-(morpholin-4-yl)piperidin-1-yl]azetidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[3-(dimethylamino)propyl]piperazin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[4-methyl-4-(4-methylpiperazin-1-yl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{4-[2-(piperidin-1-yl)ethoxy]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-5-methyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[4-(4-methylpiperazine-1-carbonyl)phenyl]-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[3-(morpholin-4-yl)azetidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-3-(propan-2-yl)-4-(4-propyl-1,4-diazepan-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-cyclobutyl-1,4-diazepan-1-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-butyl-1,4-diazepan-1-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-(4-methyl-1,4-diazepan-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[(8aR)-hexahydropyrrolo[1,2-a]pyrazin-2(1H)-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-acetylpiperazin-1-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-ethylpiperazin-1-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[4-(2-hydroxyethyl)piperazin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(dimethylcarbamoyl)piperazin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(ethoxyacetyl)piperazin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[4-(3-methoxypropyl)piperazin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-3-(propan-2-yl)-4-(4-propylpiperazin-1-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{4-[2-(2-hydroxyethoxy)ethyl]piperazin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{4-[3-(4-methyl-1,4-diazepan-1-yl)-3-oxopropyl]piperazin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(cyclohexylmethyl)piperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-(9-methyl-3,9-diazaspiro[5.5]undecan-3-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(1,4-dioxa-8-azaspiro[4.5]decan-8-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[(3R)-3-hydroxypiperidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-(4′-methyl[1,4′-bipiperidin]-1′-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{4-[2-(4-methylpiperazin-1-yl)ethyl]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[(3R)-3-(piperidin-1-yl)pyrrolidin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(diethylamino)piperidin-1-yl]-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-tert-butylpiperazin-1-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-3-(propan-2-yl)-4-{4-[1-(pyrrolidin-1-yl)ethyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{4-[(piperidin-1-yl)methyl]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{4-[(1-methylpiperidin-3-yl)methyl]piperazin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{4-[(oxolan-2-yl)methyl]piperazin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[4-(1-methoxypropan-2-yl)piperazin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-3-(propan-2-yl)-4-[3-(pyrrolidin-1-yl)azetidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-3-(propan-2-yl)-4-[4-(propan-2-yl)-1,4-diazepan-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[(3aR,6aS)-5-(2-methylpropyl)hexahydropyrrolo[3,4-c]pyrrol-2(1H)-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-ethyl-1,4-diazepan-1-yl)-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-(4-hydroxy-4-{[methyl(propan-2-yl)amino]methyl}piperidin-1-yl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{4-[methyl(propan-2-yl)amino]piperidin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[2-(diethylamino)ethyl]piperazin-1-yl}-1-(4-fluorophenyl)-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-[4-(1-methylpiperidin-4-yl)piperazin-1-yl]-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-{[(3R)-3-(methoxymethyl)pyrrolidin-1-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-{[(3R)-3-methoxypyrrolidin-1-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-{[(3S)-3-(methoxymethyl)pyrrolidin-1-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[1-(morpholin-4-yl)ethyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-cyclohexyl-4-{4-[(morpholin-4-yl)methyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-cyclohexyl-4-{4-[2-(morpholin-4-yl)ethyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-(cyclobutyloxy)-1-cyclohexyl-4-{4-[(morpholin-4-yl)methyl]phenyl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-cyclohexyl-4-[4-(pyridin-4-yl)piperazin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[2-(morpholin-4-yl)ethyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-3-(propan-2-yl)-4-{4-[(pyrrolidin-1-yl)methyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-{4-[1-(pyrrolidin-1-yl)ethyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(3-oxo-2,8-diazaspiro[4.5]decan-2-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-{4-[(2-methylpropoxy)carbonyl]piperazin-1-yl}-3-(propan-2-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(2-methoxypyridin-4-yl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(methoxymethyl)piperidin-1-yl]-1-[2-(oxan-4-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-phenyl-4-[4-(propan-2-yl)piperazin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-[2-(oxan-4-yl)pyridin-4-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(3-methylphenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[(morpholin-4-yl)methyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(3-methoxyphenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-[4-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluoro-3-methylphenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(3-fluorophenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-[3-(trifluoromethyl)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(3-fluoroazetidin-1-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(3,3-difluoropyrrolidin-1-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(3-methoxyazetidin-1-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(3,3-difluoropiperidin-1-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-{[3-(methoxymethyl)azetidin-1-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-{[(3R)-3-fluoropyrrolidin-1-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-{[(3S)-3-fluoropyrrolidin-1-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(1,4-oxazepan-4-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-{[3-(2,2-difluoroethoxy)azetidin-1-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(6-oxa-2-azaspiro[3.5]nonan-2-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(6-oxa-2-azaspiro[3.4]octan-2-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-{[(7S,8aS)-7-fluorohexahydropyrrolo[1,2-a]pyrazin-2(1H)-yl]methyl}piperidin-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(4-formyl-1,4-diazepan-1-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(2-oxa-7-azaspiro[3.5]nonan-7-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(4-methoxypiperidin-1-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(2-oxa-6-azaspiro[3.4]octan-6-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(4-formylpiperazin-1-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-{4-[(3-azabicyclo[3.1.0]hexan-3-yl)methyl]piperidin-1-yl}-3-cyclobutyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-{4-[(5-methyl-6-oxo-2-oxa-5,8-diazaspiro[3.5]nonan-8-yl)methyl]piperidin-1-yl}-1-phenyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[4-(3-fluoropyrrolidin-1-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(3-cyanoazetidin-1-yl)piperidin-1-yl]-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[4-(3-methoxypyrrolidin-1-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4-fluoro[1,4′-bipiperidin]-1′-yl)-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(4,4-difluoro[1,4′-bipiperidin]-1′-yl)-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(2-cyanomorpholin-4-yl)piperidin-1-yl]-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[4-(2-oxa-5-azabicyclo[2.2.1]heptan-5-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[2-(methoxymethyl)morpholin-4-yl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[methyl(oxan-4-yl)amino]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-{2-[(propan-2-yl)oxy]pyridin-4-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-[2-(benzyloxy)pyridin-4-yl]-3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[(morpholin-4-yl)methyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[(4-methylpiperazin-1-yl)methyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-{[4-(methoxymethyl)piperidin-1-yl]methyl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-cyano[1,4′-bipiperidin]-1′-yl)-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-{4-[4-(dimethylamino)piperidine-1-carbonyl]phenyl}-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[3-(pyrrolidin-1-yl)-1-oxa-8-azaspiro[4.5]decan-8-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-3-[(propan-2-yl)oxy]-4-{4-[4-(propan-2-yl)piperazin-1-yl]phenyl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-cyclohexyl-4-[4-(2-methylpyridin-4-yl)piperazin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-cyclohexyl-4-{6-[4-(propan-2-yl)piperazin-1-yl]pyridin-3-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-cyclohexyl-4-{4-[1-(morpholin-4-yl)ethyl]phenyl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-cyclohexyl-4-{4-[4-(propan-2-yl)piperazin-1-yl]phenyl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-cyclohexyl-4-[6-(4-cyclopropylpiperazin-1-yl)pyridin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[3-(trifluoromethyl)pyrrolidin-1-yl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[4-(3-cyanopyrrolidin-1-yl)piperidin-1-yl]-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(3-cyano[1,4′-bipiperidin]-1′-yl)-3-cyclobutyl-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(3-fluoro[1,4′-bipiperidin]-1′-yl)-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[4-(3-methoxyazetidin-1-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[3-(trifluoromethyl)[1,4′-bipiperidin]-1′-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-(3-methoxy[1,4′-bipiperidin]-1′-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(2,2-dimethylmorpholin-4-yl)piperidin-1-yl]-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-cyclohexyl-4-[6-(4-methylpiperazin-1-yl)pyridin-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-cyclohexyl-4-{6-[4-(2-methoxyethyl)piperazin-1-yl]pyridin-3-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[4-(propan-2-yl)piperazin-1-yl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-cyclohexyl-4-{4-[4-(propan-2-yl)piperazin-1-yl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3S)-4-benzyl-3-methylpiperazin-1-yl]-3-cyclobutyl-1-cyclohexyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-[(3R)-4-benzyl-3-methylpiperazin-1-yl]-3-cyclobutyl-1-cyclohexyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-[4-(4-methylpiperazin-1-yl)phenyl]-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-{4-[(4-cyclopropylpiperazin-1-yl)methyl]phenyl}-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(2-hydroxypyridin-4-yl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(4-cyclopropylpiperazin-1-yl)piperidin-1-yl]-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(9-cyclopropyl-3,9-diazaspiro[5.5]undecan-3-yl)-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[(pyrrolidin-1-yl)methyl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-[2-(difluoromethoxy)pyridin-4-yl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[9-(propan-2-yl)-3,9-diazaspiro[5.5]undecan-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid 3-cyclobutyl-4-{4-[4-(ethoxycarbonyl)piperazin-1-yl]piperidin-1-yl}-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-(4-methoxy[1,4′-bipiperidin]-1′-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]methyl-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(9-cyclobutyl-3, 9-diazaspiro[5.5]undecan-3-yl)-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[(2-methoxyethyl)(methyl)amino]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[4-(2-methoxyethyl)piperazin-1-yl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[9-(2-methoxyethyl)-3,9-diazaspiro[5.5]undecan-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-(4-hydroxy[1,4′-bipiperidin]-1′-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[4-(oxetan-3-yl)piperazin-1-yl]piperidin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[1-(propan-2-yl)octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-(1-cyclobutyloctahydro-5H-pyrrolo[3,2-c]pyridin-5-yl)-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[1-(oxetan-3-yl)octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[1-(oxan-4-yl)octahydro-5H-pyrrolo[3,2-c]pyridin-5-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-[9-(oxetan-3-yl)-3,9-diazaspiro[5.5]undecan-3-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(3,5-difluorophenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(2,2-difluoro-2H-1,3-benzodioxol-5-yl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(3,4-difluorophenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluoro-3-methoxyphenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-[4-(trifluoromethoxy)phenyl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-[3-(difluoromethoxy)phenyl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(bicyclo[4.2.0]octa-1,3,5-trien-3-yl)-3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(3-fluoro-4-methoxyphenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(3-fluoro-5-methoxyphenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-[4-(difluoromethoxy)phenyl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-[3-(1,1-difluoroethyl)phenyl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(2,5-difluorophenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-[6-(2-fluoroethoxy)pyridin-3-yl]-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-{2-[(oxan-4-yl)oxy]pyridin-4-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-{2-[(oxan-4-yl)methoxy]pyridin-4-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(2,4-difluorophenyl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(2,2-difluoro-2H-1,3-benzodioxol-4-yl)-4-[4-(morpholin-4-yl)piperidin-1-yl]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 4-(4-cyanophenyl)-1-cyclohexyl-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(morpholin-4-yl)piperidin-1-yl]-1-{6-[(propan-2-yl)oxy]pyridin-2-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-3-hydroxy-4-(4-methoxy[1,4′-bipiperidin]-1′-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-(4-fluorophenyl)-4-(4-methoxy[1,4′-bipiperidin]-1′-yl)-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 1-cyclohexyl-4-(4-{[3-(dimethylamino)azetidin-1-yl]methyl}phenyl)-3-[(propan-2-yl)oxy]-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-1-(4-fluorophenyl)-4-(9-methyl-3,9-diazaspiro[5.5]undecan-3-yl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; 3-cyclobutyl-4-[4-(ethoxycarbonyl)piperazin-1-yl]-1-(4-fluorophenyl)-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid; and 3-cyclobutyl-1-(4-fluorophenyl)-4-{4-[(2-methylpropoxy)carbonyl]piperazin-1-yl}-1H-pyrazolo[3,4-b]pyridine-6-carboxylic acid.
 33. A pharmaceutical composition comprising a therapeutically effective amount of a compound of claim 1, or a pharmaceutically acceptable salt thereof, in combination with a pharmaceutically acceptable carrier.
 34. A compound of claim 1 or a pharmaceutically acceptable salt thereof for use in medicine.
 35. A compound of claim 1 or a pharmaceutically acceptable salt thereof for use in the treatment of cystic fibrosis.
 36. A method for treating cystic fibrosis in a subject comprising administering a therapeutically effective amount of a compound of claim 1 or a pharmaceutically acceptable salt thereof, to a subject in need thereof.
 37. A pharmaceutical composition comprising a compound of claim 1 or a pharmaceutically acceptable salt thereof, one potentiator, and one or more additional correctors.
 38. A method for treating cystic fibrosis in a subject comprising administering a compound of claim 1 or a pharmaceutically acceptable salt thereof, one potentiator, and one or more additional correctors, to a subject in need thereof.
 39. A pharmaceutical composition comprising a compound of claim 1 or a pharmaceutically acceptable salt thereof, and one or more additional therapeutic agents.
 40. The pharmaceutical composition of claim 39 wherein the additional therapeutic agents are selected from the group consisting of CFTR modulators and CFTR amplifiers.
 41. The pharmaceutical composition of claim 39 wherein the additional therapeutic agents are CFTR modulators.
 42. A method for treating cystic fibrosis in a subject comprising administering a compound of claim 1 or a pharmaceutically acceptable salt thereof, and one or more additional therapeutic agents.
 43. The method of claim 42 wherein the additional therapeutic agents are selected from the group consisting of CFTR modulators and CFTR amplifiers.
 44. The method of claim 42 wherein the additional therapeutic agents are CFTR modulators. 